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1

Problems of estimating the uncertainty of water pH measurement

Dorozhovets Mykhailo, Szlachta Anna

Zeszyty Naukowe Politechniki Rzeszowskiej. Elektrotechnika

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2024

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z. 41

13--24

EN

The article analyses the main problems associated with evaluation the combined standard uncertainty of the water pH measurement by the type A and B methods. It is shown that, for a small number n of the tested water samples, the type A standard uncertainty determined by the conventional method is underestimated. Therefore, the correct expression to calculate this component of uncertainty is presented. The authors also highlighted that since in the practical measurement the influencing quantities and sensitivity coefficients are not known abso-lutely precisely, therefore their uncertainties often have to be taken into account when estimating the combined uncertainty. For this purpose the authors have propose their approach to correctly determine the type B components of combined standard uncertainty caused by not only the values of influencing quantities and sensitivity coefficients, but also their uncertainties. The proposed approaches are illustrated by estimating the uncertainty in the measurement of drinking water pH, presenting the corresponding components of measurement uncertainty budget.

2

Kształtowanie się wybranych właściwości gleby jako efekt aplikacji pulpy siarkowej z materiałami organicznym

Filipek-Mazur Barbara, Lisowska Aneta, Kulig Bogdan

Przemysł Chemiczny

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2024

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T. 103, nr 9

984--989

PL

Doświadczenie polowe przeprowadzono w latach 2018-2019 w Stacji Doświadczalnej Uniwersytetu Rolniczego w Krakowie. W I roku badania obejmowały 5 obiektów: obiekt kontrolny bez nawożenia, obiekt z na wożeniem pulpą siarkową oraz obiekty z nawożeniem pulpą siarkową w połączeniu z materiałami organicznymi. W II roku doświadczenie kontynuowano celem oceny dwóch strategii nawożenia: ponowne go zastosowania materiałów i nawozów wprowadzonych w I roku badań i wyłącznego nawożenia mineralnego NPK, w celu określenia następczego działania materiałów wykorzystanych w I roku badań. Zastosowane nawożenie miało niewielki wpływ na wartość pH gleby i zawartość węgla organicznego ogółem i korzystny wpływ na zawartość siarki siarczanowej w testowanym materiale glebowym.

EN

In the two-year field expt., the soil under corn cultivation was fertilized in the first year with S pulp or mixts. of S pulp with org. materials or not fertilized (control) in order to det. the effect of fertilization on soil parameters. In the second year, the expt. was continued to evaluate 2 fertilization strategies: reapplication of materials and fertilizers introduced in the first year of the study and exclusive mineral NPK fertilization, in order to det. the subsequent effect of materials used in the first year of the study. The applied fertilization showed a minor effect on the soil pH value and the content of total org. C, and beneficial impact on sulfate S content.

3

Influence of pH and salt solution on the sedimentation properties of finebauxite tailings

Yu Haihao, Bai Zhixiao

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 2

art. no. 186326

EN

Bauxite tailings slurry is a type of solid waste produced in the process of bauxite washing and beneficiation. It has poor engineering properties, that is, self-consolidation settlement unusually cannot be completed during several decades. To investigate the sedimentation properties of bauxite tailings, bauxite tailings slurry, phyllite residual soil, and kaolinite, we conduct sedimentation tests on these materials in varying pH and salt solution environments. The influence mechanism of the surface electrical properties of clay particles on the settlement of tailings slurry is investigated using the zeta potential test. The findings reveal that increases in the cation concentration and valence state lead to compression of the electric double layer on the surface of three types of soil particles, resulting in a decline in the repulsive potential energy and an increase in the gravitational potential energy. This in turn contributes to a reduction in the settling stable void ratio. As the pH increases, the zeta potentials of the three soils gradually decrease from positive to negative. A change in the pH at the isoelectric point, PZCedge, triggers the transformation of the kaolinite mineral arrangement. When the pH is either greater than or less than the isoelectric point, an increase or decrease in the pH results in expansion of the electric double layer of the clay particles and an increase in the pore content. The resultsof this study suggest that bauxite tailings mud is more likely to settle in an acidic environment than in an alkaline environment, thus an acidic settling environment should be utilized for bauxite tailings produced in industrial production.

4

Assessment of the effectiveness of potentiometric sensors for measuring the pH of concrete

Jaśniok Tomasz

Ochrona przed Korozją

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2024

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nr 9

261--264

EN

The paper presents the results of long-term tests of pH-metric potentiometric sensors containing metal oxides in concrete, using the example of manganese oxide. Unfortunately, their long-term effectiveness in natural conditions is not known. These tests showed their poor effectiveness in determining the pH value under variable moisture conditions of concrete. The jumps in the potential of the pH sensors resulting from changes in humidity significantly exceeded the so-called theoretical Nernst response (59.16 mV per pH unit), which disqualifies them from monitoring changes in the pH of liquids in concrete pores in natural conditions.

PL

W pracy przedstawiono wyniki długotrwałych badań pH-metrycznych czujników potencjometrycznych w betonie zawierających tlenki metali, w tym wypadku tlenek manganu. Nie ustalono dotychczas, czy działają prawidłowo po długim czasie w warunkach naturalnych. Badania wykazały ich słabą skuteczność w określaniu wartości pH przy zmiennych warunkach wilgotnościowych betonu. Wynikające ze zmiany wilgotności skoki potencjału czujników pH znacznie przekraczały tzw. teoretyczną odpowiedź Nernsta (59,16 mV na jednostkę pH), nie mogą być więc stosowane w monitorowaniu zmian pH cieczy w porach betonu w warunkach naturalnych.

5

Effect of Differences in Bio-activators and Fermentation Time on the Properties of Liquid Organic Fertilizers Based on Local Rabbit’s Urine Waste

Said Muhammad Irfan, Mustabi Jamila, Al-Tawaha Abdel Razzaq Mohammad Saeed, Sirajuddin Sitti Nurani, Azizah Nur, Al-Assaf Raha

Journal of Ecological Engineering

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2024

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Vol. 25, nr 8

264--275

EN

Rabbits, which are commonly raised as livestock in many rural areas of Asian countries, produce liquid waste called urine that can have negative environmental impacts. In order to tackle this issue, the development of technology is necessary to effectively process this waste into a form that can be utilized without causing harm to the environment. Urine contains valuable organic compounds that can be used as raw materials for the production of liquid organic fertilizer (LOF). The quality of this fertilizer is dependent on the availability of microorganism substrates and the duration of fermentation. The objective of this study is to investigate the influence of different substrates and fermentation periods on the properties of liquid organic fertilizer. The raw material used in this research is locally sourced rabbit urine. The experiments were conducted in a laboratory at the Faculty of Animal Science, Hasanuddin University, Indonesia. Three types of substrates were employed: bioactivator animal substrate (BAsb), bioactivator plant substrate (BPsb), and commercial microorganism (C-mic) as the control. Two different fermentation periods were tested: 2 weeks and 4 weeks. The data were analyzed using a completely randomized design (CRD) with factorial patterns. The results revealed that the type of bioactivator substrate had a significant impact (p<0.05) on the N-organic, C/N ratio, P2O5, and K2O content. However, pH and C-organic showed no significant effect (p>0.05). Additionally, fermentation time had a significant effect (p<0.05) on C-organic, N-organic, and the C/N ratio, but pH did not have a significant effect (p>0.05). Moreover, there was a significant interaction (p<0.05) between the substrate type and fermentation time in the LOF-RU process. The production of N-organic content from local rabbit urine yielded promising results. For the LOF-RU production process with BAsb or BPsb, fermentation periods of up to 4 weeks can be applied.

6

Proposed precision analysis of water quality monitoring embedded loT network

Boonsong Wasana, Inthasuth Tanakorn, Zulkifli Che Zalina

Przegląd Elektrotechniczny

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2023

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R. 99, nr 9

175--178

EN

Regarding the essential need for water in agriculture, water resource conservation is becoming a more critical issue that farming developers will consider. The quality instrument used for water monitoring in Farming is one factor to assist an agricultural section in achieving a high impact on their production. This article is presented the precision analysis of water quality monitoring embedded Internet of Things (IoT) Network whereby the proposed invention is a wireless embedded water monitoring system with multi-sensor. The highlight of a measuring instrument is its precision. This study demonstrates its calibration regarding the positive potential of the hydrogen ions (pH). The procedures of precision calibration are related to programming and actual measurement in several tests. The results found that the pH sensor with IoT communication only has a significantly lower erroneous of 0.77%.

PL

Jeśli chodzi o podstawowe zapotrzebowanie na wodę w rolnictwie, ochrona zasobów wodnych staje się coraz ważniejszą kwestią, którą będą rozważać deweloperzy rolnictwa. Instrument jakości używany do monitorowania wody w rolnictwie jest jednym z czynników pomagających sekcji rolniczej w osiągnięciu wysokiego wpływu na ich produkcję. W artykule przedstawiono precyzyjną analizę wbudowanej sieci Internet of Things (IoT) do monitorowania jakości wody, w której proponowanym wynalazkiem jest bezprzewodowy wbudowany wieloczujnikowy system monitorowania wody. Najważniejszym elementem przyrządu pomiarowego jest jego precyzja. To badanie demonstruje jego kalibrację w odniesieniu do dodatniego potencjału jonów wodorowych (pH). Procedury kalibracji dokładności są związane z programowaniem i rzeczywistym pomiarem w kilku testach. Wyniki wykazały, że czujnik pH z komunikacją IoT ma tylko znacznie niższy błąd wynoszący 0,77%.

7

Effect of pH value on effectiveness of biopolymer-based treatment of bauxite mine slurry

Meng Jian Ping, Li Shanmei, Yan Rongtao, Wei Changfu

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 3

art. no. 167949

EN

Effective dehydration and flocculation of mine slurries or sludge is important for nonferrous metal industries and environmental engineering. However, the mechanisms for the flocculation of slurry remain largely unclear. This paper presents the results of a series of flocculation tests, which was conducted on the slurry suspensions treated by xanthan gum (flocculant) at different pH values. It is shown that the settlement rate of mine slurry particles can be accelerated by adding xanthan gum, and the maximum sedimentation rate was obtained at a pH value of 5.9, and the final volume of flocs is significantly increased due to the addition of the flocculant. In addition, the settlement rates of xanthan gum-treated slurry suspensions at the pH values of 3, 5 and 7 decrease slightly compared with the reference slurry suspensions with pH=5.9, and the slurries remained stable as suspensions at the pH value of 9 and 11. The zeta potential measurement and SEM image analysis show that flocculation occurs primarily due to electrostatic attraction between slurry particles and the flocculants, and the bridging effect between the carboxylic groups in the side chains of xanthan gum molecule and the suspension particles.

8

Study of the effectiveness of the new inhibitor in different aggressive media

Gurbanov Huseyn R., Talybov Gulahmad M., Adygezalova Mehpara B., Zhang Yu X.

Nafta-Gaz

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2023

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R. 79, nr 7

478--483

EN

The corrosion protection effect of the new S-1 reagent in media with the pH values of 2.0, 4.0, 6.0, as well as carbon dioxide and hydrogen sulfide added separately and combined to the mentioned media, was first tested under laboratory conditions. The protective effect of reagent S-1 was weak in the corrosion medium without hydrogen sulfide and carbon dioxide. However, as the acidity of the medium and the concentration of the reagent increases, the corrosion protection efficiency of the inhibitor also increases. The highest effect is observed at pH = 2.0 and reagent concentration of 30 mg/l. The corrosion protection effect of the reagent reaches 97% under these conditions. In the media with pH = 4.0 and pH = 6.0 without carbon dioxide and hydrogen sulfide, the protective effect of the inhibitor at the optimal concentration of 30 mg/l is 66% and 64%, respectively. In the medium with added carbon dioxide, the protective effect of inhibitor S-1 decreases at pH = 2.0 and, on the contrary, increases at the values of pH = 4.0 and pH = 6.0. Also, as the pressure of carbon dioxide in the medium increases, the protective effect of inhibitor S-1 increases. When hydrogen sulfide is added to the medium, it causes an increase in the corrosion rate and the protection efficiency of inhibitor S-1. However, in the medium without inhibitor, the increase of hydrogen sulfide concentration only up to CH2S = 400 mg/l is accompanied by an increase in the corrosion rate at all values of pH. The addition of 1000 mg/l of hydrogen sulfide to the corrosion medium leads to the decrease in the corrosion rate in the medium without inhibitors and a slight decrease in the protective effect at the concentration of the inhibitor Cinh = 10 mg/l. As the concentration of inhibitor S-1 increases in the medium with the addition of carbon dioxide and hydrogen, its corrosion protection effect also increases. In the range of Cinh = 10–30 mg/l, when PCO2 = 0.5 atm and CH2S = 200 mg/l, the protective effect is estimated at 38–99%, and when CH2S = 1000 mg/l, it is estimated at 17–79%. At PCO2 = 1.0 atm, the value of protective effect is 22–95% and 14–76%, and finally at PCO2 = 2.0 atm, the value of the corrosion protection effect of inhibitor S-1 is estimated at 44–92% and 15–75%, respectively. The coexistence of carbon dioxide and hydrogen sulfide in an aggressive medium leads to an increase in the protective effect of inhibitor S-1 compared to the medium containing only carbon dioxide, and reduces it in comparison to the medium with hydrogen sulfide. An increase in carbon dioxide pressure in the presence of hydrogen sulfide causes a decrease in the protective effect of inhibitor S-1. The protective effect of inhibitor S-1 is lower in the medium with hydrogen sulfide concentration of 1000 mg/l compared to a concentration of 200 mg/l. This case is also observed in the carbon dioxide free medium.

PL

Działanie antykorozyjne nowego odczynnika S-1 w agresywnych mediach o pH 2,0; 4,0; 6,0, a także dwutlenku węgla i siarkowodoru dodawanych osobno lub łącznie do tych mediów, zostało najpierw zbadane w warunkach laboratoryjnych. Działanie ochronne odczynnika S-1 było słabe w środowisku korozyjnym bez siarkowodoru i dwutlenku węgla. Jednak wraz ze wzrostem kwasowości medium i stężenia odczynnika wzrasta również skuteczność inhibitora w ochronie przed korozją. Najlepsze działanie antykorozyjne odnotowano przy wartości pH = 2,0 i stężeniu odczynnika 30 mg/l. Skuteczność ochronna odczynnika wynosi wówczas 97%. W medium o pH = 4,0 i pH = 6,0 bez dwutlenku węgla i siarkowodoru skuteczność ochronna inhibitora przy optymalnym stężeniu 30 mg/l wynosi odpowiednio 66 i 64%. W medium z dodatkiem dwutlenku węgla działanie ochronne inhibitora S-1 maleje przy wartości pH = 2,0 i odwrotnie wzrasta przy wartościach pH = 4,0 i pH = 6,0. Ponadto, wraz ze wzrostem ciśnienia dwutlenku węgla w środowisku wzrasta skuteczność ochronna inhibitora S-1. Dodanie siarkowodoru do medium powoduje wzrost tempa korozji i skuteczności ochronnej inhibitora S-1. Jednak w medium bez inhibitora wzrostowi stężenia siarkowodoru nawet do tak niskiej wartości jak CH2S = 400 mg/l towarzyszy wzrost tempa korozji przy wszystkich wartościach pH. Dodanie 1000 mg/l siarkowodoru do medium korozyjnego prowadzi do zmniejszenia tempa korozji w medium bez inhibitorów i nieznacznego zmniejszenia działania ochronnego przy stężeniu inhibitora Cinh = 10 mg/l. Wraz ze wzrostem stężenia inhibitora S-1 w medium z dodatkiem dwutlenku węgla i siarkowodoru, zwiększa się również jego działanie antykorozyjne. W zakresie Cinh = 10–30 mg/l, gdy PCO2 = 0,5 atm i CH2S = 200 mg/l, skuteczność ochronną szacuje się na 38–99%, natomiast przy CH2S = 1000 mg/l na 17–79%. Dla PCO2 = 1,0 atm skuteczność ochronna wynosi od 22–95% do 14–76%, a przy PCO2 = 2,0 atm skuteczność antykorozyjną inhibitora S-1 szacuje się odpowiednio na 44–92% i 15–75%. Jednoczesne występowanie dwutlenku węgla i siarkowodoru w agresywnym medium zwiększa skuteczność ochronną inhibitora S-1 w stosunku do medium zawierającego tylko dwutlenek węgla i zmniejsza ją w porównaniu do medium z siarkowodorem. Wzrost ciśnienia dwutlenku węgla w obecności siarkowodoru powoduje zmniejszenie skuteczności ochronnej inhibitora S-1. Ulega ona także zmniejszeniu w środowisku o stężeniu siarkowodoru 1000 mg/l w porównaniu do stężenia 200 mg/l. Ten przypadek obserwuje się również w środowisku bez dodatku dwutlenku węgla.

9

The Influence of Abiotic Factors on Organisms-Hydrobionts of Activated Sludge

Baimukasheva Shynar, Issayeva Akmaral U., Antkowiak Wojciech, Aitimova Ainazhan, Altybayeva Zhansaule, Syrlybekkyzy Samal, Suleimenova Botagoz, Koishina Akmaral

Journal of Ecological Engineering

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2023

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Vol. 24, nr 10

125--133

EN

Rational use of water resources is one of the urgent problems for arid regions of Kazakhstan. The biocenosis of activated sludge of urban wastewater treatment plants in Zhanaozen periodically encounters stressful situations associated with violation of the operating mode of equipment or emergency discharges of toxicants into the wastewater treatment plant system. It has been established that with sharp fluctuations in the physicochemical parameters of aqueous solutions, protozoal organisms are primarily eliminated from the composition of activated sludge. This pattern was noted with an increase in the content of ammonium nitrogen, phosphorus, monoethanolamine and pH fluctuations in wastewater. Under the conditions of a 10-month period of active insolation in Western Kazakhstan, the species diversity of the algoflora of activated sludge correlates with the duration of daylight hours; it was found that diatoms predominate in the autumn-winter period of the year, whereas blue-green and green algae predominate in the spring-summer period.

10

Heavy Metals in Soil and Plants During Revegetation of Coal Mine Spoil Tips and Surrounded Territories

Kucher Larisa, Krasnoshtan Igor, Nedilska Uliana, Muliarchuk Oksana, Manzii Olena, Menderetsky Vadim, Boroday Vira, Beregniak Evgeniy, Voitsekhivskyi Volodymyr, Myronycheva Olena

Journal of Ecological Engineering

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2023

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Vol. 24, nr 7

234--245

EN

Coal mining in Donbas is a global problem as it causes the destabilization of ecological landscapes. Spoil tips, covering almost 52% of the territory, alter the topography of the land, affect the ecosystem, and decrease soil fertility. The soils become degraded and are unsuitable for agricultural use. The occupation of the Donetsk region by the Russian Federation has suspended the observation and research of man-made influence on this territory, which is a major concern for the scientific community. To reduce the negative impact of spoil tips, it is necessary to slow down the process of pyrite oxidation and the formation of toxic substances, as well as the migration of heavy metals due to erosion. Biological reclamation with grass and woody plants can help in achieving this goal. Another urgent issue is the constant supervision and assessment of the suitability of the bedrock of coal mines for agricultural use. The study investigated the total and mobile content of heavy metals in the rock samples from the “South Donbaska-1” mine, ordinary chernozem (background soil), and vegetation growing on the spoil tip. The results showed that the content of Co, Cr, Cu, and Fe in the rock of the spoil tip is higher than in the background soils. The content of heavy metals gradually decreases as the distance from the spoil tip increases. The content of Pb in ordinary chernozem and rock is practically the same, indicating its active migration. An analysis of the biomass of plant samples growing on the spoil tip showed that the content of Co, Cu, and Zn was within the limits of the threshold limiting values. However, the content of other studied elements exceeded the permissible norms. The research results provide information on the ecological state of the spoil tip and can be used for recreational as well as reclamation works in these areas.

11

Heavy Metals Contamination of Local and Imported Rice in Semarang, Central Java, Indonesia

Wahyuningsih Nur Endah, Setiawan Henry, Nabiha Puteri Inandin, Kartasurya Martha Irene, Azam Mahalul

Journal of Ecological Engineering

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2023

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Vol. 24, nr 7

49--60

EN

This study defined the heavy metal concentration in rice, a commonly consumed staple food in Indonesia that is domestically produced and also imported from other countries due to its high demand. A total of six rice samples, comprising of four domestic and two foreign were randomly taken from Semarang stores and analyzed using the Atomic Absorbance Spectrometer (AAS). The laboratory results revealed that three varieties of rice, two from Indonesia (MW and PW; 0.561 and 0.456 mg/kg, each), and one from the United States (B; 0.307 mg/kg), exceeded the Indonesian dietary standard for lead (Pb) (SNI). Furthermore, the concentration of chromium (Cr) in two rice that are imported (B, 0.241 mg/kg and J, 0.723 mg/kg) were greater than the 0.2 mg/kg threshold established by the Chinese government. However, all samples had acceptable levels of As and Hg, and none had detectable levels of Cd. In terms of pH levels, domestically produced rice had a wider range (3.88–5.78) compared to imported rice (4.96–5.68). Although locally grown and imported rice had acceptable levels of LCR, only one local rice sample and two imported rice samples exceeded the Target Hazard Quotient (THQ) as well as Hazard Index (HI) values. In conclusion, consuming heavy metals contamination rice on a regular basis poses carcinogenic as well as non-carcinogenic health risks.

12

Effect of Coal Mining Waste and Its Mixtures with Sewage Sludge and Mineral Wool on Selected Properties of Degraded Anthropogenic Soil

Żukowska Grażyna, Myszura-Dymek Magdalena, Roszkowski Szymon, Bik-Małodzińska Marta

Journal of Ecological Engineering

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2023

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Vol. 24, nr 10

340--350

EN

The aim of the study was to evaluate the effect of coal mining waste and its mixtures with municipal sewage sludge and waste rock wool from cover crops on the formation of selected properties of degraded anthropogenic soil. Under the conditions of a pot experiment, coal mining waste and its mixtures with 2.5 and 5% sewage sludge and mixtures supplemented with 1% addition of waste rockwool from cover crops were introduced (in a ratio of 1:1) into the degraded anthropogenic soil. White mustard was grown on the substrates in the first year and maize in the second year. The pH, EC, and sorption properties were determined in soil samples taken before of the plants and after their harvest. The results showed that the addition of coal mining waste and its mixtures with municipal sewage sludge and waste rock wool improved the soil pH and sorption properties. The management of coal mining waste and waste optimising its properties for the production of fertilizing agents can be an effective strategy within a circular economy, which at the same time will increase the efficiency of the management of degraded and poor-quality soils.

13

Analysis of the Solubility of a Support Filament Made of a Copolymer of Vinyl Alcohol and Butanediol in Aqueous Solutions with Variable pH

Paśnikowska-Łukaszuk Magdalena, Urzędowski Arkadiusz, Wlazło Magda, Mikušová Dominika, Zaburko Jacek

Journal of Ecological Engineering

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2023

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Vol. 24, nr 12

201--207

EN

3D printing is a modern technology that enables the creation of three-dimensional objects from various thermoplastic copolymers. One of the challenges of 3D printing is providing adequate support for complex shapes that may fall apart or deform during the printing process. Traditionally, support materials are used for this purpose, which are difficult to remove after printing and difficult to dispose of. This work focuses on the analysis of the solubility of the BVOH support filament in solutions with different pH values. In particular, the influence of pH on the dissolution time of the BVOH (Butenediol Vinyl Alcohol Co-polymer) copolymer in aqueous solutions and its influence on changes in the PETG base material from which the samples were printed were examined. It was found that the BVOH material combined with PETG is easily soluble in an alkaline environment.

14

The Study of the Germination Behavior of Forage Species on Substrates Taken from the Soil of Awleigatt National Park in Mauritania

Abidine Mohamed Mahmoud, Cheikh Lemane Mohamed, Dallahi Youssef, Baba Mohamed Lemine, Mahmoud El Weila Mohamed, Soulé Ahmedou, Vadel Ahmedou

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 6

257--269

EN

Awleigatt National Park (ANP) is a zoological site ensuring both the conservation and restoration of biodiversity on a national scale. In this perspective, the ANP has set as one of its ambitious objectives the autonomy in fodder needs. The objective of this work was to study the adaptability of three forage species (Medicago sativa, Acacia senegal and Dolichos lablab) to the edaphic conditions of the NAP. The adopted approach was to characterize three types of representative ANP soil substrates in order to develop an interpolation map of EC conductivity and pH data. Subsequently, the germination behavior of the three species was studied in the laboratory on three substrates taken from the study area (Dune, Dune flank and Interdune) in the absence and presence of NaCl (0, 50 and 100 Mm). The obtained results show that the soils are basic and the electrical conductivity is higher in the inter-dune substrate. The mapping of the study area corroborates the experimentally obtained data. Germination behavior shows that germination is best on dune and dune flank substrates. The addition of high concentrations of NaCl (100mM) shows that Dolichos lablab is the most resistant to salinity. Medicago sativa and Acacia senegal show low germination capacity both in the absence and in the presence of NaCl, most likely reflecting a low embryonic longevity of the seeds used. The parameters deduced from the germination kinetics curve show that the adverse effect of salinity in the three species is observed at all three germination phases (TL, GSS and CG). As a result, the effect of salinity on germination of all three species is both osmotic and toxic.

15

Survival of Bacterial Pathogen Isolated from Urine in Surface Water in Sebou River Estuary (Morocco)

Ech-Chayeb Kaouatar, Auajjar Nabila, Lihi Khadija, Attarassi Benaissa

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 3

71--78

EN

Hospital effluents are one of the main sources of contamination of groundwater and rivers if they are collected by urban networks and sent to wastewater treatment plants (WWTP), without prior treatment. These effluents are potential vectors of resistant pathogenic bacteria and could contribute to the spread of these strains in the environment. The Sebou River is used as a receptacle for domestic water treatment from the city of Kenitra. The main of the study is to analyze the effect of pH (8.2, 7.5, and 6.5) at a temperature of 22°C on the behavior of three pathogenic bacteria isolated from urine in filtered and sterilized water Sebou River. The water of Sebou River was inoculated with the three bacterial strains tested by a concentration that varied from 106–108 CFU/mL, then incubated for 30 days. The results of the obtained analyses showed that the pH affects the survival of the tested bacterial strains. For some strains, the alkaline pH at 22°C is a beneficial effect that prolongs survival. The main finding from the study was that the three strains of Escherichia coli at a pH of 8.2 have a better survival that reaches the 7th day and then declines. On the other hand, with a strain of Klebsiella pneumoni and Staphylococcus aureus at pH 7.5, the action effects are harmful; it limits survival to 72 hours and causes a rapid decrease in the number of bacteria. We have shown in our experiments that bacteria survive much better at low temperatures and basic pH.

16

Effects of Pore Fluid's pH on the Physico-Mechanical Behavior of High Plasticity Silt

Dahal Bhim Kumar, Pokharel Santosh, Basnet Saroj, Dahal Uttam, Sah Shivam Kumar, Neopane Sneha, Adhikari Sinam, Timalsina Susmita

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 8

202--215

EN

Acid rain and water pollution are alarming threats, necessitating the study of their influences in different environmental aspects. This study investigates the effects of pore water’s pH on the behavior of high plasticity silt. Samples with varied pore fluid pH were tested for Atterberg limits, unconfined compressive strength on the 9th, 18th, and 27th curing days. Particle size distribution and zeta potential were assessed on the 27th day on strength tested samples. The test showed that the soil properties change with the pH of the pore fluid and the days the sample were cured for. The particle size distribution revealed that higher silt and clay fractions were present in acidic and alkaline conditions respectively. Liquid limit varied irregularly with different pH conditions. On all test days, the plastic limit increased under acidic and alkaline conditions compared to neutral conditions. The Unconfined compressive strength and zeta potential were observed to be low in the acidic and alkaline conditions compared to the neutral condition. The result infers that the dissolution of cementitious elements in acidic and alkaline conditions reduces the long-term strength of the soil. These findings encourage geotechnical engineers to evaluate the pH characteristics of the pore fluids during geotechnical analysis.

17

Effect of crystallinity and surface silanol groups on rheological properties of different sepiolites

Çınar Mustafa, Gülgönül Ilhan, Ozdemir Orhan, Çelik Mehmet S.

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 153947

EN

In this study, differences in the rheological properties of three different types of brown sepiolites (K1, K2, and K3) along with one beige (B) sepiolite with different physicochemical properties were explained based on their crystallinity and level of surface silanol groups. Towards this aim, SEM images, XRD and chemical analyses, cation exchange capacity (CEC), and water absorption tests were conducted along with surface area measurements and time-dependent pH profiles. The pH profiles at 3% by wt. revealed that each sepiolite sample attained the equilibrium at different times. These differences showed a parallel behavior with the degree of crystallinity. While sepiolite with better crystallinity (K1) was rather slow in reaching the equilibrium pH, the sepiolites with poor crystallinity (B and K3) reached their equilibrium pH more quickly. The rheological studies conducted with different sepiolites at 3% solids concentration exhibited time-dependent flow of the Bingham plastic model and thixotropic. Differences observed in the rheological behavior of sepiolites were found to correlate with the fiber size, CEC, surface area, and water absorption. The results further indicated that sepiolites with low crystallinity or high level of surface silanol groups (K3 and B sepiolites) show the best rheological properties.

18

Seasonal carbonate system vis-à-vis pH and Salinity in selected tropical estuaries: Implications on polychaete diversity and composition towards predicting ecological health

Sarathy Palanivel Partha, Bharathidasan Veeraiyan, Murugesan Perumal, Selvaraj Palanichamy, Punniyamoorthy Rengasamy

Oceanologia

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2022

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No. 64 (2)

346--362

EN

Salinity and pH play a fundamental role in structuring spatial patterns of physical properties, biota, and biogeochemical processes in the estuarine ecosystem. In this study, the influence of salinity-pH gradient and carbonate system on polychaete diversity in Ennore, Uppanar, Vellar, and Kaduvaiyar estuaries was investigated. Water and sediment samples were collected from September 2017 to August 2018. Univariate and multivariate statistical analyses were employed to define ecological status. Temperature, salinity, pH, and partial pressure of carbon-di-oxide varied between 21 and 30°C; 29 and 39 ppt; 7.4 and 8.3; and 89.216 and 1702.558 µatm, respectively. PCA and CCA results revealed that DO, chlorophyll, carbonate species, and sediment TOC have a higher influence on polychaete community structure. Forty-two species such as Ancistrosyllis parva, Cossura coasta, Eunice pennata, Euclymene annandalei, Lumbrineris albidentata, Capitella capitata, Prionospio cirrifera, P. pinnata, P. cirrobranchiata, and Notomastus sp. were found dominantly in all estuaries. Shannon index values ranged between 1.619 (UE-1) and 3.376 (VE-2). Based on these findings, high levels of carbonate species and low pH have a greater impact on polychaete diversity and richness values. The results of the AMBI Index revealed that stations UE-1, UE-2, UE-3 in Uppanar, EC-1, EC-2 in Ennore indicate “moderately disturbed”, while other stations are under the “slightly disturbed” category. This trend was quite evident in M-AMBI as well.

19

Water Quality Assessment of Anchar Lake, Srinagar, India

Ashraf Samiyah, Kaur Simarjot, Singla Sandeep

Civil and Environmental Engineering Reports

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2022

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Vol. 32, no. 1

88--115

EN

The aim of this study was to ascertain the current condition of the Anchar lake water body in the Indian state of J&K in terms of water quality using some main parameters such as pH, TDS, EC, DO, and nitrates content. For the years 2019 and 2020, samples were obtained for two seasons: summer and winter. The quantitative analysis of the experimental results indicates a general increasing trend and considerable variance in nitrates content, as well as a gradual decrease in pH, indicating that the lake's acidity is increasing, but only within the basicity range, with real values approaching neutrality: TDS and EC content suggest a very favorable situation, but when the overall parameters are tested, they show a defect. Since the sampling sites were well aerated, the dissolved oxygen content showed a growing pattern, and as a result, this metric proved to be useless in deciding the overall scenario in the lake. In the winter, the longitudinal trend line indicates a 10% decrease in pH, while in the summer, it shows a 4.4 percent decrease in pH. In winters, the longitudinal trend line reveals a 6.7 percent growth in nitrate content, while summers see a marginal decline. In the winter, the longitudinal trend line shows a 7% rise in dissolved oxygen, while in the summer, it shows a uniform trend.

20

Multi-molecule imaging and inter-molecular imaging in nuclear medicine

Shimazoe Kenji, Uenomachi Mizuki

Bio-Algorithms and Med-Systems

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2022

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Vol. 18, no. 1

127--134

EN

Multi-molecule imaging and inter-molecular imaging are not fully implemented yet, however, can become an alternative in nuclear medicine. In this review article, we present arguments demonstrating that the advent of the Compton positron emission tomography (Compton-PET) system and the invention of the quantum chemical sensing method with double photon emission imaging (DPEI) provide realistic perspectives for visualizing inter-molecular and multi-molecule in nuclear medicine with MeV photon. In particular, the pH change of InCl3 solutions can be detected and visualized in a three-dimensional image by combining the hyperfine electric quadrupole interaction sensing and DPEI. Moreover, chemical states, such as chelating, can be detected through angular correlation sensing. We argue that multi-molecule and chemical sensing could be a realistic stream of research in future nuclear medicine.