buffer capacity
Recently Published Documents


TOTAL DOCUMENTS

718
(FIVE YEARS 118)

H-INDEX

44
(FIVE YEARS 4)

2022 ◽  
Author(s):  
Tatiana Minkina ◽  
Dina Nevidomskaya ◽  
Aleksey Sherbakov ◽  
Victor Chaplygin ◽  
Yurii Litvinov ◽  
...  

Heavy metals (HM) are among the most hazardous soil pollutants. The intensity of accumulation and distribution of HM in soils directly depends on the ecological conditions of pedogenesis and its buffering properties. At the same time, a significant accumulation of HM in the soil as a result of anthropogenic impacts reduces the buffering capacity of the soil and its resistance to pollution. The purpose of this work was to assess the buffering capacity of soils to HM pollution in the Don River delta and the coast of the Taganrog Bay of the Sea of Azov undergoing the great anthropogenic impact. The buffer capacity of experimental soils was carried out using the Il’in’s method (1995), based on the calculation of the inactivation ability of soils: organic matter, clay fraction (particle size < 0.01 mm), carbonates, sesquioxides, and pH. The content of HM was compared with soil Clarke and the maximum permissible concentration of HM in soils accepted in the Russian Federation. It was found that the experimental soils could be ordered by buffer capacity value as following (in decreasing order): haplic chernozem ≥ alluvial-meadow light loamy ≥ solonchak > alluvial-meadow sandy and sandy loamy > sandy primitive soil ≥ stratified alluvial soil. Keywords: trace elements, contamination, impact territories


Author(s):  
Florent Gauvin ◽  
Vesta Tsao ◽  
Joost Vette ◽  
Henricus Jozef Hubertus Brouwers

This research aims to study mycelium-based composites (MBC) by assessing their performance as foam-like wall insulation material. Various substrates have been selected to get optimized performance of the composite. Results showed that a prolonged growing period arose a denser mycelium outer layer in MBC, which rendered better water resistance due to the hydrophobicity of mycelium. Thermal conductivity and mechanical properties are highly dependent on substrate choices than other parameters of MBC, which coincided with the literature. Additionally, influences of accelerated aging test and moisture buffer capacity of MBC were first studied in this research. The results indicated that MBC not only maintained good functional performance after the accelerated aging test (i.e. drying and wetting cycles) but also constituted good moisture buffer capacity. This means that MBC has key material essences to apply as internal wall insulation material and become one of the layers in vapor-permeable building envelope systems to passively regulate indoor relative humidity and thermal comfort.


2022 ◽  
Vol 961 (1) ◽  
pp. 012076
Author(s):  
Marwa Alaa Abbas ◽  
Mustafa Abduljalil Ebraheem

Abstract The ability of an organism or system to restore form and position elastically following a disturbance or interruption of any type is the true meaning of resilience. How often does the term “resilience” appear in regional or metropolitan contexts to allude to a local socio-economic system’s ability to rebound from a shock or disruption? Resilience can be characterized in a variety of ways. Another term is buffer capacity, which refers to a system’s ability to absorb disturbances and the quantity of disturbance before the system’s structure is altered by modifying the variables and processes that influence behavior. The study concludes that industrial activities affect the city in general and the city’s environment in particular through the pollutants caused by these activities. In order to develop planning solutions to address any change in the city under the concept of environmental resilience, the researchers paid attention to this aspect, which provides treatments, solutions, and suggestions in order to preserve the city from crises and Industrial activities that negatively affect the environment of the city, that the city of Bazian contains industrial factories for the manufacture of cement and bricks because it is rich in raw materials. Of the importance of industrial activities that contribute to the production of an economic resource for the region, but there are deficiencies in the ecological systems that maintain the direct impact of these industries on the environment, the insufficiency of regulations and legislation within the framework of industrial determinants.


Author(s):  
Farah Bechir ◽  
Mariana Pacurar ◽  
Adrian Tohati ◽  
Simona Maria Bataga

The oral cavity has specific and individualized characteristics, with pH, saliva flow, buffer capacity, temperature, and microorganisms content influencing oral health. Currently, the prevalence of gastroesophageal reflux disease (GERD) is constantly increasing. The objective of this study was to evaluate and compare the saliva quantity at 5 min, salivary pH, and salivary buffer capacity in patients with and without GERD, necessary for establishing the correct dental treatment plan. A Saliva-Check Buffer (GC) kit was used for the determination of salivary variables. The total number of 80 patients included in the study were divided into a study group and a control group, each containing 40 patients. Saliva quantity at 5 min was lower in patients suffering from GERD. The salivary pH of these patients turned to acid values compared to the salivary pH of controls, where the values were within the normal range. In patients with GERD, the determined salivary buffer capacity was low or very low. The use of the Saliva-Check Buffer (GC) kit is a simple, easy, non-invasive and patient-accepted method, which can also be used in the dentist’s office to assess the saliva buffer capacity and pH, variables that are important for establishing a correct dental treatment plan.


Author(s):  
Agata Trzcionka ◽  
Henryk Twardawa ◽  
Katarzyna Mocny-Pachońska ◽  
Rafał Korkosz ◽  
Marta Tanasiewicz

There has been an increasing number of patients diagnosed with chronic diseases. Many of those diseases determine changes in patients’ social and even professional life. The aim of the present work was to analyze saliva and oral mucosa parameters in adult patients diagnosed with chronic diseases. A total of 228 patients took part in the research. A total of 180 patients were hemodialyzed in Diaverum dialysis stations, and there were 48 patients from the Conservative Dentistry with Endodontics Clinic of the Academic Centre of Dentistry of Silesian Medical University in Bytom and patients from the dentistry division of the Arnika Clinic in Zabrze not diagnosed with any such diseases. Selected saliva parameters (secretion, pH and buffer capacity) and mucosa status were examined. In order to obtain information regarding xerostomia, patients were given a questionnaire. Patients assigned to the control group rarely used water to make swallowing easier or used candies to lessen the feeling of oral cavity dryness. They also rarely suffered from eye dryness. The feeling of dryness also did not influence their social life. The amount of produced saliva was higher in the control group. There was a significantly lower percentage of patients with a low buffer capacity of saliva. There were no differences in terms of saliva pH values between the two groups of patients. A significantly lower number of patients were diagnosed with ecchymosis, candidiasis, scrotal tongue and mechanical damages. Patients diagnosed with chronic diseases need to be provided with long-term care.


Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 4026
Author(s):  
Alexey V. Dubrovskii ◽  
Aleksandr L. Kim ◽  
Egor V. Musin ◽  
Bulat R. Ramazanov ◽  
Sergey A. Tikhonenko

Polyelectrolyte microcapsules, which are obtained by the method of alternate adsorption of oppositely charged polyelectrolytes onto colloidal particles of micron size, are widely used in science and industry. Nevertheless, the properties of microcapsules are still poorly understood. In particular, there is no information in the literature on the buffer capacity. However, information on the presence of a buffer capacity and an understanding of its mechanisms can both simplify the use of microcapsules and expand the scope of their application. In this regard, the buffer capacity of various types of microcapsules was studied. It was found that polyelectrolyte microcapsules consisting of polyallylamine, and polystyrene sulfonate have a buffer capacity. In addition, in an acidic medium, the buffer capacity of microcapsules containing BSA is significantly greater than that of microcapsules without protein. This is due to the fact that BSA contributes to the buffering of microcapsules. Differences in the behaviour of the buffer capacity of microcapsules with the composition (PAH/PSS)3 and (PSS/PAH)3 were found. In addition, a hypothesis has been proposed that regions of unbound polyallylamine are responsible for the buffering properties of polyelectrolyte microcapsules. This hypothesis is confirmed by the fact that incubation of microcapsules in 0.5 M NaCl increases the amount of unbound polyallylamine, which leads to an increase in the buffer capacity of microcapsules at alkaline pH values higher than the buffer capacity of capsules in an aqueous solution.


2021 ◽  
Vol 901 (1) ◽  
pp. 012044
Author(s):  
G V Stepanova ◽  
M V Volovik

Annotation It is shown that the buffer capacity of dry matter of alfalfa of the first cut in the flowering phase is 5.66-5.94 mol / liter. With an increase in the content of crude protein and crude ash by 1%, it increases by 0.14-0.40 and 0.49-0.86 mol / liter, respectively, with an increase in the content of soluble carbohydrates by 1%, it decreases by 1.44 mol / liter … The dry matter of the second cut alfalfa has a high forage quality. The content of crude protein from the stemming-beginning of budding phase to the flowering phase is in the range of 23.44-20.20%, crude ash 9.24-8.10%, while the content of crude fiber is reduced to 22.92-29.01%, dry matter - up to 20.84-26.00%. The buffer capacity of dry matter reaches 9.69-7.23 mol / liter. The main influence on the buffer capacity is exerted by the mineral composition of the dry matter. An increase in the content of crude ash by 1% increases the buffer capacity of dry matter by 0.55 ± 0.16 - 1.36 ± 0.14 mol / l, an increase in the content of crude protein by 1% increases the buffer capacity by 0.15 ± 0.06 - 0.39 ± 0.14 mol / liter.


Sign in / Sign up

Export Citation Format

Share Document