scholarly journals Waste hazard properties HP 4 ‘Irritant’ and HP 8 ‘Corrosive’ by pH, acid/base buffer capacity and acid/base concentration

Detritus ◽  
2021 ◽  
pp. 5-15
Author(s):  
Pierre Hennebert
Keyword(s):  
Buffer Capacity ◽  
Buffering Capacity ◽  
Atmospheric Co2 ◽  
Acid Base ◽  
Product Method ◽  
Alkaline Waste ◽  
Natural Carbonation ◽  
Technical Recommendations

European "Technical Recommendations" have proposed, in addition to the use of substance concentrations, the use of a pH (≤ 2 or ≥ 11.5) and an acid / base buffering capacity to classify waste into according to their hazardous properties HP 4 'Irritant' and HP 8 'Corrosive'. Buffer capacity refers to a 2018 UK classification guide referring to the 'corrosive' level of a method proposed in 1988 for substances and preparations but not retained in EU regulations. The different methods of classifying products and wastes in terms of corrosivity or irritation are compared. The waste method using pH and buffering capacity is expressed as an acid / base concentration and compared to the product method (CLP). The “corrosive” level of 1988 corresponds to an average acid / base concentration ≥ 14.4Ͽie 14 times less severe than CLP (acid / base concentration ≥ 1Ͽ These methods were applied to five alkaline wastes (pH ≥ 11.5). Minimum pH waste is not classified by both methods, and three higher pH wastes are classified by both methods. Intermediate waste is classified by CLP but not by the proposed waste method. In order not to innovate and create a new divergence between products and waste, it seems preferable to use the product regulations for HP 4 and HP 8. Fortunately, the elimination of the danger HP 4 and HP 8 from acidic or alkaline waste can be obtained by neutralization (possibly by other wastes), including for alkaline wastes by (natural) carbonation by atmospheric CO2.

THE CONTRIBUTION OF LACTATE AND PHOSPHATE ANIONS TO THE BUFFER PROPERTIES OF TISSUE HOMOGENATES OF BREAST ADENOCARCINOMA

2019 ◽  
Vol 65 (5) ◽  
pp. 684-690
Author(s):  
Margarita Barsukova ◽  
Yekaterina Khomutova ◽  
Yevgeniy Khomutov
Keyword(s):  
Mammary Gland ◽  
Buffer Capacity ◽  
Tumor Tissue ◽  
Mammary Adenocarcinoma ◽  
Breast Adenocarcinoma ◽  
Acid Base ◽  
Adjacent Tissue ◽  
Tumor Tissues ◽  
Tissue Homogenates ◽  
Phosphate Anions

The article discusses the role of conjugated lactic acid/ lactate anion (LacH/Lac-) and dihydrogenphosphate anion/ hydrogenphosphate anion (H2PO4-/HPO42-) pairs in the formation of the buffer properties of tissue as a factor determining pH. The buffer properties of homogenates of the tissue of adenocarcinoma of the mammary gland and the adjacent tissue were quantitatively characterized by the buffer capacity which was determined by potentiometric titration. The concentrations of acid anions were determined spectrophotometrically. The material was biopsy specimens of mammary gland adenocarcinoma (T1-4, N0-1, M0) and adjacent tissue of 22 patients aged from 33 to 75 years. It was found that the buffer capacity of tumors is in 2.5 times higher than in normal tissue. It was established that for the tumor tissue, the buffer capacity of the LacH/Lac- system is in 3 times higher, and the buffer capacity of the H2PO4-/HPO42-system is in 2.5 times greater than for normal untransformed tissue. Concentrations of lactate anions (1,93 ± 0,50 vs 0,57 ± 0,22; p <0.001) and phosphate anions (2,54 ± 0,39 vs 0,70 ± 0,19; p <0,001) in homogenates of the tumor tissue were significantly higher in tumor tissue in comparison with the adjacent tissue. A strong correlation was found between the concentration of phosphate anions and the buffer capacity for tumor tissue (r = 0,857; p = 0,002) and for adjacent tissue (r = 0,917; p <0,001). The correlation between the concentration of lactate anions and the buffer capacity for tumor tissues can be estimated as average (r = 0,626; p = 0,053), while it is absent for the adjacent tissue (r = 0,494; p = 0,147). The results suggest that the acid-base properties of homogenates of mammary adenocarcinoma tissues are determined by two buffer systems: LacH/Lac- and H2PO4-/HPO42-, while the intracellular acid-base homeostasis of non-transformed tissues is mainly determined by the H2PO4-/HPO42- system.

Variable charges of a red soil from different depths: Acid-base buffer capacity and surface complexation model

2018 ◽  
Vol 159 ◽  
pp. 107-115 ◽  
Author(s):  
Ying Wang ◽  
Pengfei Cheng ◽  
Fangbai Li ◽  
Tongxu Liu ◽  
Kuan Cheng ◽  
...  
Keyword(s):  
Buffer Capacity ◽  
Surface Complexation ◽  
Red Soil ◽  
Acid Base ◽  
Surface Complexation Model ◽  
Different Depths

scholarly journals Biogeochemical processes and buffering capacity concurrently affect acidification in a seasonally hypoxic coastal marine basin

2015 ◽  
Vol 12 (5) ◽  
pp. 1561-1583 ◽  
Author(s):  
M. Hagens ◽  
C. P. Slomp ◽  
F. J. R. Meysman ◽  
D. Seitaj ◽  
J. Harlay ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Primary Production ◽  
Water Column ◽  
Bottom Water ◽  
Substantial Reduction ◽  
Buffering Capacity ◽  
Total Alkalinity ◽  
Acid Base ◽  
Data Set ◽  
Ph Fluctuations

Abstract. Coastal areas are impacted by multiple natural and anthropogenic processes and experience stronger pH fluctuations than the open ocean. These variations can weaken or intensify the ocean acidification signal induced by increasing atmospheric pCO2. The development of eutrophication-induced hypoxia intensifies coastal acidification, since the CO2 produced during respiration decreases the buffering capacity in any hypoxic bottom water. To assess the combined ecosystem impacts of acidification and hypoxia, we quantified the seasonal variation in pH and oxygen dynamics in the water column of a seasonally stratified coastal basin (Lake Grevelingen, the Netherlands). Monthly water-column chemistry measurements were complemented with estimates of primary production and respiration using O2 light–dark incubations, in addition to sediment–water fluxes of dissolved inorganic carbon (DIC) and total alkalinity (TA). The resulting data set was used to set up a proton budget on a seasonal scale. Temperature-induced seasonal stratification combined with a high community respiration was responsible for the depletion of oxygen in the bottom water in summer. The surface water showed strong seasonal variation in process rates (primary production, CO2 air–sea exchange), but relatively small seasonal pH fluctuations (0.46 units on the total hydrogen ion scale). In contrast, the bottom water showed less seasonality in biogeochemical rates (respiration, sediment–water exchange), but stronger pH fluctuations (0.60 units). This marked difference in pH dynamics could be attributed to a substantial reduction in the acid–base buffering capacity of the hypoxic bottom water in the summer period. Our results highlight the importance of acid–base buffering in the pH dynamics of coastal systems and illustrate the increasing vulnerability of hypoxic, CO2-rich waters to any acidifying process.

scholarly journals Correlation between pH, buffering capacity, calcium and dental caries in schoolchildren

2018 ◽  
Vol 63 (01) ◽  
pp. 63-68
Author(s):  
Efka Zabokova Bilbilova ◽  
Ana Sotirovska Ivkovska ◽  
Olivera Sarakinova ◽  
Olga Kokoceva Ivanovska ◽  
Natasha Stavreva
Keyword(s):  
Dental Caries ◽  
Free Group ◽  
Buffer Capacity ◽  
Saliva Sample ◽  
Buffering Capacity ◽  
Active Group ◽  
Ph Buffering ◽  
Ph Values ◽  
Salivary Ph ◽  
Ph Buffering Capacity

The aim of this study was to determine salivary pH, buffering capacity and calcium levels in caries-free and caries-active children. We examined 80 children of both genders, 15 years of age. Subjects were divided into four groups as follows: caries-free females, caries-active females, caries-free males, caries-active males; each group consisted of 20 subjects. The unstimulated saliva sample was collected by the spitting method and then pH, buffering capacity and calcium in saliva was measured. The results showed that mean level of buffering capacity of saliva was decreased significantly in the caries-active group as compared to caries-free group. The obtained data showed that the mean levels of pH and calcium were decreased in the caries-active group as compared to the caries-free group, but the difference was not statistically significant. The saliva with its constituents plays an important role in maintaining oral and especially dental health. Salivary pH values were found to be higher in the caries-free group. In our study, there was no significant correlation of pH values and caries activity with gender. Buffer capacity values were significantly lower in the caries-active group than in the caries-free group. There were significant differences when the groups were compared in the caries-active group where buffer capacity values were higher in boys than in girls. Calcium content of saliva was higher in the caries-free group. The results obtained in this study related to the values of the pH, buffering capacity and calcium in saliva, may serve as parameters for determining the caries risk patients, and accordingly to plan and carry appropriate caries preventive measures. Keywords: saliva, dental caries, pH, buffer capacity, calcium

scholarly journals The Buffer Effect of Different Wood Species and the Influence of Oak on Panel Composites Binders

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1540 ◽  
Author(s):  
Franco Policardi ◽  
Marion Thebault
Keyword(s):  
Present Article ◽  
Wood Species ◽  
Internal Bond ◽  
Buffer Capacity ◽  
Urea Formaldehyde ◽  
Buffering Capacity ◽  
Buffer Effect ◽  
Wood Panel ◽  
Oak Chips ◽  
Industrial Operations

The buffer action of certain wood species can intensely affect the curing and hardening of some thermosetting wood adhesives. The present article presents a quantification of such buffering effects, determined under controlled conditions, in various wood species. The buffer capacity of oak has been found to be rather extreme and is likely to affect quite heavily the ability of urea-formaldehyde (UF) and melamine-urea-formaldehyde (MUF) wood panel adhesives in industrial operations. A variation of the buffer capacity of furnishes containing between 0% and 30% oak chips has been investigated. This was correlated with the internal bond (IB) strength of MUF bonded laboratory particleboards. The wood mixture buffering capacity increases with the oak content, while the panel IB strength decreases.

scholarly journals Influence of training intensity on adaptations in acid/base transport proteins, muscle buffer capacity, and repeated-sprint ability in active men

2016 ◽  
Vol 121 (6) ◽  
pp. 1290-1305 ◽  
Author(s):  
Cian McGinley ◽  
David J. Bishop
Keyword(s):  
Lactate Threshold ◽  
Buffer Capacity ◽  
Transport Protein ◽  
Confidence Limits ◽  
Training Intensity ◽  
Acid Base ◽  
Repeated Sprint Ability ◽  
Repeated Sprint ◽  
Sprint Ability

McGinley C, Bishop DJ. Influence of training intensity on adaptations in acid/base transport proteins, muscle buffer capacity, and repeated-sprint ability in active men. J Appl Physiol 121: 1290–1305, 2016. First published October 14, 2016; doi: 10.1152/japplphysiol.00630.2016 .—This study measured the adaptive response to exercise training for each of the acid-base transport protein families, including providing isoform-specific evidence for the monocarboxylate transporter (MCT)1/4 chaperone protein basigin and for the electrogenic sodium-bicarbonate cotransporter (NBCe)1. We investigated whether 4 wk of work-matched, high-intensity interval training (HIIT), performed either just above the lactate threshold (HIITΔ20; n = 8), or close to peak aerobic power (HIITΔ90; n = 8), influenced adaptations in acid-base transport protein abundance, nonbicarbonate muscle buffer capacity (βmin vitro), and exercise capacity in active men. Training intensity did not discriminate between adaptations for most proteins measured, with abundance of MCT1, sodium/hydrogen exchanger (NHE) 1, NBCe1, carbonic anhydrase (CA) II, and CAXIV increasing after 4 wk, whereas there was little change in CAIII and CAIV abundance. βmin vitro also did not change. However, MCT4 protein content only increased for HIITΔ20 [effect size (ES): 1.06, 90% confidence limits × / ÷ 0.77], whereas basigin protein content only increased for HIITΔ90 (ES: 1.49, × / ÷ 1.42). Repeated-sprint ability (5 × 6-s sprints; 24 s passive rest) improved similarly for both groups. Power at the lactate threshold only improved for HIITΔ20 (ES: 0.49; 90% confidence limits ± 0.38), whereas peak O2 uptake did not change for either group. Detraining was characterized by the loss of adaptations for all of the proteins measured and for repeated-sprint ability 6 wk after removing the stimulus of HIIT. In conclusion, 4 wk of HIIT induced improvements in each of the acid-base transport protein families, but, remarkably, a 40% difference in training intensity did not discriminate between most adaptations.

The pH of K-deficient muscle

1959 ◽  
Vol 196 (4) ◽  
pp. 811-818 ◽  
Author(s):  
Robert E. Eckel ◽  
Andrew W. Botschner ◽  
Don H. Wood
Keyword(s):  
Indirect Method ◽  
Direct Method ◽  
Dry Weight ◽  
Buffering Capacity ◽  
Muscle Proteins ◽  
Acid Base Balance ◽  
Acid Base ◽  
Weak Bases ◽  
Base Balance ◽  
K Deficiency

The acid-base balance of muscle from control and K-deficient rats was studied. From the measured buffering capacity, 8–11 mEq excess of anions or deficit of cations would be required to acidify 100 gm fat-free dry weight of muscle, 0.5 pH units. No evidence of increased organic acids, increased anionic equivalence of muscle proteins, or of decreased concentrations of weak bases which are potential cations in cell acidosis was found. This evidence, supplemented with data in the literature, fails to account for the cell acidosis reported in the literature. Reliability of the ‘chloride space’ as a measure of the extracellular phase of muscle in K deficiency has been confirmed by showing its agreement with the ‘raffinose space.’ The cell pH has then been calculated from the distribution of CO2 in muscle (indirect method) and from the pH of muscle homogenates (direct method) in control and K-deficient animals. Control and K-deficient muscle pH's are, respectively, 6.89 and 6.83 by the direct method, and 7.11 and 7.05 by the indirect method.

scholarly journals AMINOMETHANSULFONIC AND ALKYLAMINOMETHANSULFONIC BUFFER SYSTEMS

2019 ◽  
Vol 85 (9) ◽  
pp. 3-16
Author(s):  
Ruslan Khoma ◽  
Alim Ennan ◽  
Aleksandr Chebotarev ◽  
Sergey Vodzinskii
Keyword(s):  
Chemical Analysis ◽  
Electron Donor ◽  
Concentration Ratio ◽  
Buffer Capacity ◽  
Water Systems ◽  
Acid Base ◽  
Buffer Action ◽  
Ph Values ◽  
Biochemical Studies ◽  
Medium Acidity

The investigations of acid-base interactions in aminomethanesulfonic acid (AMSA)–potassium aminomethanesulfonate–water and alkylaminomethanesulfonic acid–potassium alkylaminomethane-sulfonate–water systems, where alkyl are methyl (MeAMSA), N-(2-hydroxyethyl) (HEAMSA), n-propyl (n-PrAMSA), n-butyl (n-BuAMSA), tert-butyl (t-BuAMSA), n-heptyl (n-HpAMSA) and benzyl (BzAMSA) were performed in temperature range 293–313 К. Buffer action pH limits were determined and the buffer capacity of these systems was estimated.Based on the evaluation of buffer action pH limits of aminomethansulfonic acids, it has been found that with the help of n-PrAMSA and n-BuAMSA, it was possible to maintain the medium acidity in the range of physiological pH values throughout the range of investigated temperatures.As the temperature rises, the pH of the lower buffer limit increases for AMSA and n-BuAMSA systems, while for HEAMSA, t-BuAMSA, n-HpA-MSA and BzAMSA decreases. The value of the pH of the upper buffer threshold for all tested systems decreases during their heating. With the increase of the electron-donor properties of the N-substituent in the AMSA–MeAMSA–HEAMSA–t-BuAMSA series, the value of their electronegativity decreases to result in lowering of the pH values of the lower buf-fering action limit of these systems. For the more lipophilic N-substituents (n-C4H9, n-C7H15 and C6H5CH2), this regularity is not typical.It has been established that with increasing the CYAMSK/CYAMSA concentration ratio, the buffer capacity of YNHCH2SO3H–YNHCH2SO3K–H2O systems with hydrophilic aminomethansulfonic acids (Y = H, CH3 and HOCH2CH2) increases. For systems with lipophilic n-PrAMSA and t-BuAMSA, their buffer capacity doesn’t change at 0.4 ≤ QKOH/QYAMSA ≤ 1.0.The obtained data on the buffer capacity of the investigated systems is recommended for use in chemical analysis, microbiological and biochemical studies.

scholarly journals BUFFER SYSTEMS BASED ON AMINOMETANESULPHONATE AND MONOETHANOLAMMONIUM N-ALKYLAMINOMETHANESULPHONATES

2021 ◽  
Vol 26 (2(78)) ◽  
pp. 22-31
Author(s):  
R.E. Khoma ◽  
А. А-А. Ennan ◽  
T. S. Bienkovska ◽  
L. T. Osadchiy ◽  
E. L. Roy
Keyword(s):  
Buffer Capacity ◽  
Acid Base ◽  
Ph Buffering ◽  
Ph Values ◽  
Titration Curves ◽  
Upper Limit ◽  
Empirical Function ◽  
Ionic Associates ◽  
Aminomethanesulfonic Acids ◽  
Acidic Region

The limits of the pH buffering action (pHbuff) of YNHCH2SO3H – NH2CH2CH2OH –H2O (Y = H, CH3, HOCH2CH2, t-С4H9 and C6H5CH2) were determined and their buffer capacity (p) for monoethanolamine (MEA) was estimated in the temperature range 293–313 K. For systems with aminomethanesulfonic acid (AMSA), its N‑methyl, N‑hydroxyethyl (HEAMSA) and N‑benzyl (BzAMSA) derivatives, an increase in temperature leads to a decrease in the pH values of the lower limit of the buffering action of their solutions with monoethanolamine; in the case of N‑tert-butylaminomethanesulfonic acid (t-BuAMSA) – to an increase in the specified characteristic. An increase in temperature for systems with the most hydrophobic t-BuAMSA and BzAMSA (in comparison with other studied aminomethanesulfonic acids) leads to a decrease in the pH values of the upper limit of the buffer action. A decrease in the YNHCH2SO3H and NH2CH2CH2OH concentration leads to a shift in the boundaries of the pH of the buffering action to a more acidic region. The nature of the influence of the empirical function, combining their acid-base properties and lipophilicity (рKа + lgPow), on the concentration dependence of the buffer capacity according to MEA was revealed. It is shown that the buffering effect of the studied systems is due to the presence, in addition to the systems N‑alkylammoniummethanesulfonate – N‑alkylaminomethanesulfonate and 2-hydroxyethylammonium – monoethanolamine, ionic associates (pairs and triples). The position of the extrema on the graphical π=f(CMEA)/QYAMSA) dependencies for systems with hydrophilic AMSA and HEAMSA coincides with the position of the first minima on the differential titration curves dpH/dV = f(CMEA)/QYAMSA). Substitution of MEA to potassium aminomethanesulfonate leads to a shift in the pH buffering action to a more acidic region and increases the buffer capacity of the resulting systems.

scholarly journals Acid-Base Regulation in the Atlantic Hagfish Myxine Glutinosa

1991 ◽  
Vol 161 (1) ◽  
pp. 201-215 ◽  
Author(s):  
D. G. McDONALD ◽  
V. CAVDEK ◽  
L. CALVERT ◽  
C. L. MLLLIGAN
Keyword(s):  
Sulphuric Acid ◽  
Blood Volume ◽  
Ammonium Sulphate ◽  
Extracellular Space ◽  
External Environment ◽  
Buffering Capacity ◽  
Acid Excretion ◽  
Acid Base ◽  
Myxine Glutinosa ◽  
Acid Base Status

Blood acid-base status and net transfers of acidic equivalents to the external environment were studied in hagfish, Myxine glutinosa, infused with ammonium sulphate (4mequivkg−1 NH4+) or with sulphuric acid (3mequiv kg−1 H+). Hagfish extracellular fluids (ECF) play a greater role in acid-base regulation than in teleosts. This is because hagfish have a much larger blood volume relative to teleosts, despite a relatively low blood buffering capacity. Consequently, infusion of ammonium sulphate produced only half of the acidosis produced in marine teleosts in comparable studies, and hagfish readily tolerated a threefold greater direct H+ load. Furthermore, the H+ load was largely retained and buffered in the extracellular space. Despite smaller acid-base disturbances, rates of net H+ excretion to the external environment were, nonetheless, comparable to those of marine teleosts, and net acid excretion persisted until blood acid-base disturbances were corrected. We conclude that the gills of the hagfish are at least as competent for acid-base regulation as those of marine teleosts. The nature of the H+ excretion mechanism is discussed.

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