Periodico Tche QuimicaPub Date : 2021-07-28DOI: 10.52571/PTQ.v18.n38.2021.06_SURYADI_pgs_62_84.pdf
Taufik Suryadi, Hijra Novia Suardi, H. Zain, Z. Hayati, B. Yanti
{"title":"KNOWLEDGE AND ATTITUDES REGARDING ETHICAL AND MEDICOLEGAL ISSUES IN HANDLING THE COVID-19 PANDEMIC AMONG RESIDENT DOCTORS AT ZAINOEL ABIDIN HOSPITAL, ACEH, INDONESIA","authors":"Taufik Suryadi, Hijra Novia Suardi, H. Zain, Z. Hayati, B. Yanti","doi":"10.52571/PTQ.v18.n38.2021.06_SURYADI_pgs_62_84.pdf","DOIUrl":"https://doi.org/10.52571/PTQ.v18.n38.2021.06_SURYADI_pgs_62_84.pdf","url":null,"abstract":"Background: Coronavirus Disease 2019 (COVID-19) has spread throughout the world to become a pandemic, making the entire health sector overwhelmed. Hospitals as health service facilities continuously strive to provide optimal service to patients with the confirmed COVID-19 infection. Resident doctors usually handle COVID-19 patients at the Zainoel Abidin Hospital (ZAH). As the front liner in handling the COVID-19 pandemic, these resident doctors must have adequate knowledge and good attitudes in dealing with COVID-19 patients, especially regarding ethical and medicolegal. Aim: This study aims at finding out the level of knowledge and attitudes of resident doctors in dealing with the COVID-19 pandemic at the ZAH, Aceh. Methods: This was a cross sectional study conducted among resident doctors (n=80) in the ZAH during November-December 2020 with a self-administered online questionnaire. It had been tested for validity by experts with a Content Validity Ratio / CVR of 0.738 and reliability of 0.732. The data were analyzed using the frequency distribution test (univariate) and the Chi square correlation test (bivariate). Results and Discussion: The results show that the majority of respondents had inadequate knowledge of ethical and medicolegal issues in handling the COVID-19 pandemic (70.0%); however, they had a positive attitude in overcoming ethical and medicolegal issues, i.e.77.5%. The chi square statistical test result shows no correlation between knowledge and attitude with a p-value of 0.077 (p-value >0.05). Conclusions: Therefore, it can be concluded that the theoretical knowledge of doctors was not sufficient to identify ethical and medicolegal issues, but the attitude in dealing with ethical and medicolegal issues was satisfactory. This result offers a new opportunity and challenge to increase the awareness of doctors in applying their knowledge and attitudes towards handling the COVID-19 pandemic.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47652468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Periodico Tche QuimicaPub Date : 2021-07-28DOI: 10.52571/PTQ.v18.n38.2021.11_GERASIMOV_pgs_149_163.pdf
A. Gerasimov, I. Semenycheva, O. Belaia, E. Volchkova, A. Gorobchenko
{"title":"ESTIMATION OF THE VALUE OF THE COVID-19 BASIC REPRODUCTIVE NUMBER AND THE EFFECT OF ANTI-EPIDEMIC MEASURES AND “SEASONAL FACTOR” ON THIS VALUE","authors":"A. Gerasimov, I. Semenycheva, O. Belaia, E. Volchkova, A. Gorobchenko","doi":"10.52571/PTQ.v18.n38.2021.11_GERASIMOV_pgs_149_163.pdf","DOIUrl":"https://doi.org/10.52571/PTQ.v18.n38.2021.11_GERASIMOV_pgs_149_163.pdf","url":null,"abstract":"Background: The emergence of COVID-19 has led to increased attention to mathematical models of epidemiology, one of the main parameters of which is the basic reproductive number R0. Its value determines both the dynamics of the incidence and the level of anti-epidemic measures. Therefore, it is desirable to have a fairly accurate method for assessing R0 for each day. Aim: Develop a methodology for determining the R0 value for COVID-19, taking into account a reasonably rapid and significant change in its value over time. Methods: a method for calculating reproduction number R0 was proposed for assessing COVID-19 R0, taking into account the change in the contagiousness of the infected people during the infectious process. Results and Discussion: In Russia in June-August 2020, the reproduction rate was slightly less 1, but in September R0 began to grow, exceeded 1, which was caused a noticeable increase in the incidence. During June in Brazil, R0 stabilized at a value of 1. The activity of transmission of the pathogen is influenced by seasonal changes in the reproduction rate R0 and the level of community immune status. Based on the assessment of the dynamics of the incidence of other pneumonia, it was found that the change of R0 during the year is about 10%, with a minimum in summer. Conclusions: while maintaining the current activity of anti-epidemic measures due to seasonal factors of the activity of the transmission mechanism and accumulation of the immune individuals in the coming months, the situation in the Russian Federation will worsen with an increase in the incidence doubled within six months, and in Brazil in six months — improve with a decrease in the incidence ten times. However, the dynamics of the incidence will be determined primarily by the work of the administration and health authorities and the conscientiousness of citizens.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45467520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Periodico Tche QuimicaPub Date : 2021-07-28DOI: 10.52571/ptq.v18.n38.2021.05_harjum_pgs_47_61.pdf
Harjum, A. Utomo, Mitrayana
{"title":"DESIGN OF EXTRA CAVITY PHOTOACOUSTIC SPECTROMETER BASED ON BLUE DIODE LASER IN NO2 (NITROGEN DIOXIDE) GAS DETECTION","authors":"Harjum, A. Utomo, Mitrayana","doi":"10.52571/ptq.v18.n38.2021.05_harjum_pgs_47_61.pdf","DOIUrl":"https://doi.org/10.52571/ptq.v18.n38.2021.05_harjum_pgs_47_61.pdf","url":null,"abstract":"Background: NO2 detection is necessary because NO2 is an air pollutant causing photochemical smog and acid rain. In addition, respiratory diseases are caused by high levels of NO2 in the inhaled air. Aim: The purpose of this study was to detect NO2 using PAS utilizing Arduino Uno, an easy, simple, and low-cost research. Methods: The detection of Nitrogen Dioxide (NO2) gas with a Photoacoustic Spectrometer (PAS) using an Arduino Uno microcontroller has been carried out. The PAS system uses a blue diode laser with a wavelength of 450 nm as the radiation source because this wavelength is suitable for NO2 gas. The intensity of the laser beam is modulated using a modulation system with an on-off scheme using the Arduino Uno. The modulation frequency has been varied to get the maximum detection frequency. The photoacoustic cell used was a single resonator photoacoustic cell with type H. Sound sensor and photodiode were used in this measurement. The amplification of the signal was done by utilizing the Lock-in amplifier, and the constant time of Lock-in amplifier was also determined to optimize the PAS. Nitrogen gas was used to detect background signal. Results and Discussion: From the photoacoustic spectrometer optimization, the results obtained were a laser diode frequency of 1,000 Hz with a duty cycle of 50% and a Lock-in amplifier amplification of 10,000 times with a constant time of 3.3 ms. The maximum concentration reached in this measurement was 6 ppm. The background signal achieved in this measurement was 0.00002 V/W. The lowest detection limit achieved in this measurement was 0.0064 ppm.Conclusion: The gas sample containers containing NO2 with larger sizes tend to have a greater concentration. Sometimes, the NO2 concentration of the large sample gas container was overtaken by the small sample container.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45251379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Periodico Tche QuimicaPub Date : 2021-07-28DOI: 10.52571/ptq.v18.n38.2021.07_delgado_pgs_85_99.pdf
G. Delgado, P. Delgado-Niño, E. Quintero
{"title":"THE QUATERNARY CHALCOGENIDE COMPOUND Ag2FeGeSe4: A REVISION OF THEIR CRYSTAL STRUCTURE AND MAGNETIC PROPERTIES","authors":"G. Delgado, P. Delgado-Niño, E. Quintero","doi":"10.52571/ptq.v18.n38.2021.07_delgado_pgs_85_99.pdf","DOIUrl":"https://doi.org/10.52571/ptq.v18.n38.2021.07_delgado_pgs_85_99.pdf","url":null,"abstract":"Background: Quaternary compounds bellowing to the I2-II-IV-VI4 system are of considerable technological interest due to their possible use in the preparation of solar cell and thermoelectric materials devices. In recent years, considerable attention has been focused on the detailed study of quaternary chalcogenide compounds related to the chalcopyrite compounds, particularly AgInSe2, which has emerged as a leading material for the preparation of photovoltaic devices due to their potential applications in solar cell technology. Aims: This work focuses on synthesis, chemical analysis, thermal study, magnetism measurement, and crystal structural characterization of the quaternary semiconductor Ag2FeGeSe4, an essential member of the family I2-II-IV-VI4. Methods: This material was synthesized by the melt and anneal technique. The chemical analysis was carried out by scanning electron microscopy (SEM) and differential thermal analysis (DTA). Magnetic susceptibility () as a function of temperature and magnetization as a function of the magnetic field were also performed, and crystal structure analysis was made employing the Rietveld method with powder X-ray diffraction data. Results and Discussion: The preparation confirms the formation of the quaternary compound with stoichiometric 2:1:1:4 according to the chemical analysis. This quaternary compound melt at 1015 K, and show an antiferromagnetic behavior with Neel temperature TN of 240 K. The Debye temperature (D) estimated for this compound was 194 K. The quaternary chalcogenide compound Ag2FeGeSe4 crystallizes in the orthorhombic space group Pmn21, Z = 4, with unit cell parameters: a = 7.6478(1) Å, b = 6.5071(1) Å, c = 6.4260(1) Å, and V = 319.79(1) Å3, in a wurtzite-stannite arrangement with a Cu2CdGeS4-type structure, which is characterized by a three-dimensional arrangement of slightly distorted AgSe4, FeSe4, and GeSe4 tetrahedra connected by corners. In this structure, each Se atom is coordinated by four cations located at the corners of a slightly distorted tetrahedron, and each cation is tetrahedrally bonded to four anions. Conclusions: The melt and anneal method remains effective for preparing compounds chalcogenides as the quaternary Ag2FeGeSe4, a new member of I2-II-IV-VI4 family of semiconductors, which crystallizes in the non-centrosymmetric space group Pmn21 with diamond-like structure. The crystal structure information of this compound allows explaining their magnetic properties, which in combination with its semiconductor properties make this material a potential aspirant for different applications, mainly in solar cells.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43396925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Periodico Tche QuimicaPub Date : 2021-07-28DOI: 10.52571/ptq.v18.n38.2021.8_zabashta_pgs_100_122.pdf
S. Zabashta
{"title":"THE IMPACT OF INTENSIVE RAISING OF AUSTRALIAN HOLSTEIN HEIFERS ON THE PHYSICOCHEMICAL PROPERTIES OF COW MILK","authors":"S. Zabashta","doi":"10.52571/ptq.v18.n38.2021.8_zabashta_pgs_100_122.pdf","DOIUrl":"https://doi.org/10.52571/ptq.v18.n38.2021.8_zabashta_pgs_100_122.pdf","url":null,"abstract":"Background: The study of growth, development and productivity features of imported cattle from Australia to the Krasnodar Territory is of great scientific and practical interest, which is topical. Since the productive features of the imported genotypes have not been studied sufficiently, not only in the farms of the Krasnodar Territory but also in other regions of Russia, they require further, more in-depth study and improvement under the new conditions of feeding and housing. Aim: The research aimed to study the influence of intensive rearing of replacement heifers of the Holstein breed of Australian selection on cow milk quality indicators. Methods: The studies were conducted at Artex-Agro LLC, Kushchevsky District of the Krasnodar Territory, concerning the descendants of the imported Australian Holstein cattle. Sixty-four heifers were selected for the study. The experimental replacement heifers were raised using the enhanced milk feeding rates and the Cellobacterin probiotic product. They were raised intensively and inseminated when they were 14 months old. The milk productivity of cows and the physicochemical properties of milk were studied during three lactations after calving. Results and Discussion: The milk productivity of the cows from the experimental groups has exceeded one of their herd mates from the control group by 450 – 1,360 kg. The best indicators of the physicochemical properties of milk have been determined in the milk of the cows raised from the heifers fed with 450 kg of the whole milk during the first 50 days until they were six months old. Conclusions: The authors believe that intensive rearing of replacement heifers positively affected the degree of development of their gastrointestinal tract and improved the level of milk yield and its physicochemical parameters.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45947931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Periodico Tche QuimicaPub Date : 2021-07-28DOI: 10.52571/ptq.v18.n38.2021.14_malyshev_pgs_188_213.pdf
V. Malyshev, Yana F. Nurgalieva, E. Moiseeva
{"title":"COMPARATIVE STUDY OF EMPIRICAL CORRELATIONS AND EQUATIONS OF STATE EFFECTIVENESS FOR COMPRESSIBILITY FACTOR OF NATURAL GAS DETERMINATION","authors":"V. Malyshev, Yana F. Nurgalieva, E. Moiseeva","doi":"10.52571/ptq.v18.n38.2021.14_malyshev_pgs_188_213.pdf","DOIUrl":"https://doi.org/10.52571/ptq.v18.n38.2021.14_malyshev_pgs_188_213.pdf","url":null,"abstract":"Introduction: Today, there are four main groups of methods for calculating the compressibility factor of natural gas: experimental measurements, equations of state, empirical correlations, modern methods based on genetic algorithms, neural networks, atomistic modeling (Monte Carlo method and molecular dynamics). A correctly chosen method can improve the accuracy of calculating gas reserves and predicting its production and processing. Aim: To find the optimal methods for calculating the z-factor following the characteristic thermobaric conditions. Methods: To determine the best method for calculating the compressibility factor, the effectiveness of using various empirical correlations and equations of state to predict the compressibility factor of hydrocarbon systems (reservoir gases and separation gases) of various compositions were evaluated by comparing numerical results with experimental data. Results and Discussion: Based on 824 experimental values of the compressibility factor for 235 various gas mixtures in the pressure range from 0.1 to 94 MPa and temperatures from 273 to 437 K, the optimal equation of state and empirical correlation dependence for accurate z-factor prediction was found. It is shown that for all gas mixtures the Peng-Robinson equation of state with the shift parameter and Brusilovsky equation of state allow achieving best results. For these methods, the average absolute relative error does not exceed 2%. Among the correlation dependences, the best results are shown by the Sanjari and Nemati Lay; Heidaryan, Moghadasi and Rahimi correlations with an error not exceeding 3%. Conclusions: It was found that for the proposed methods, the reduced pressure has a more significant effect on the accuracy of the calculated values than the reduced temperature. It is shown that when studying acid gas mixtures with a carbon dioxide content of more than 10%, the equations of state better describe the phase behavior of the system in comparison with empirical correlations.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41348004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Periodico Tche QuimicaPub Date : 2021-07-28DOI: 10.52571/ptq.v18.n38.2021.01_sheudzhen_pgs_1_14.pdf
A. Sheudzhen, O. Gutorova, G. Petrik, V. Slyusarev, O. Podkolzin
{"title":"OXIDATION-REDUCTION PROCESSES IN THE SOILS OF RICE AGROCENOSES OF THE KUBAN REGION (RUSSIA)","authors":"A. Sheudzhen, O. Gutorova, G. Petrik, V. Slyusarev, O. Podkolzin","doi":"10.52571/ptq.v18.n38.2021.01_sheudzhen_pgs_1_14.pdf","DOIUrl":"https://doi.org/10.52571/ptq.v18.n38.2021.01_sheudzhen_pgs_1_14.pdf","url":null,"abstract":"Background: The studies were carried out on the Maryano-Cheburgolsky irrigation array in the Krasnoarmeisky district of the Krasnodar Territory. Aim: This work aims to study the oxidation-reduction processes and activity of iron compounds in meadow-chernozem and meadow-boggy soils of rice agrocenoses of the Kuban region. Methods: Soil samples were taken from paddy fields occupied by rice and perennial grasses, in which the pH value, redox potential (Eh, mV), magnetic susceptibility (χ×10-3 S.I. units), and the content of active iron compounds (FeO and Fe2O3, mg/100 g) were determined. Results and Discussion: The reductive processes created in the soils of rice fields after flooding led to the transformation of poorly soluble Fe2O3 compounds into more active reaction forms of FeO. The maximum content of FeO and the minimum amount of Fe2O3 were recorded during the period of negative Eh values. The maximum reduction of iron in meadow-boggy and meadow-chernozem soils was achieved by the phase of flowering of rice plants at Eh = -127, pH = 7.36 units, rH2 = 10 and Eh = -152...-167 mV, pH = 6.89-7.10 units, rH2 = 9, respectively. Conclusions: In the soil of permanent rice cultivation, the dynamics of Eh and iron compounds are similar to the fields of rice crop rotation. In non-flooded soils of rice fields under perennial grasses, the oxidative regime prevails, and the transformation of iron compounds is not expressed. The minimum values of χ coincide with the maximum content of ferrous iron in soils at negative Eh values, which corresponds to the rice flowering phase. Correlation coefficients of χ with Eh, FeO, and Fe2O3 equal from +0.66 to +0.75, from -0.69 to -0.84, and from +0.74 to +0.77, respectively. The χ value increases in the soil under crops of perennial grasses with a predominance of oxidative processes. The correlation coefficient between χ and Fe2O3 equals from +0.83 to +0.90.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44775479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Periodico Tche QuimicaPub Date : 2021-07-28DOI: 10.52571/ptq.v18.n38.2021.02_mubasir_pgs_15_26.pdf
Yazid Mubasir, S. Supriyadi, R. M. Lia
{"title":"DEVELOPING PHYSICS GRAPH LEARNING MEDIA IN THE CONCEPT OF KINEMATICS AND ITS ASSESSMENT USING TUG-K (TEST OF UNDERSTANDING GRAPHS IN KINEMATICS)","authors":"Yazid Mubasir, S. Supriyadi, R. M. Lia","doi":"10.52571/ptq.v18.n38.2021.02_mubasir_pgs_15_26.pdf","DOIUrl":"https://doi.org/10.52571/ptq.v18.n38.2021.02_mubasir_pgs_15_26.pdf","url":null,"abstract":"Background: Assessment to determine the ability to master GLB and GLBB charts, namely the Test of Understanding Graphs in Kinematics (TUG-K). Through TUG-K which is adjusted to basic competencies, teachers can formulate indicators of competency achievement. Aim : This study aimed to develop Physics Graph learning media (GraFIS) on the kinematics concept describe the effectiveness of learning after using GraFIS media and describe students' perceptions of learning using GraFIS media and assessing using TUG-K. Methods: This research is an R and D research. The developed applications used HTML5 technology that can be published on the web app. and mobile app. The application was applied to 143 respondents in grade X MIPA of SMA Negeri 3 Purworejo. Data collection was conducted by giving validation sheets to material experts, media experts, students' questionnaire responses, to provide input on the products developed. Result and Discussion: The results of the research were in the form of graFIS application as a suitable medium for use. The results of implementation in teaching and learning activities through lesson plans that had been prepared showed that the effectiveness of learning using the GraFIS application was still in the low category with a normalized score gain of 0.03, which meant that it still needed revision and improvement. The analysis results of differences in pretest and posttest scores using Shapiro-Wilk obtained data that were not normally distributed, with Sig. 0.015 <0.05. Therefore, testing continued using the Wilcoxon Signed Rank Test. It was obtained the values of Asymp. Sig. (2-tailed) <0.05, which interpreted that there was a significant difference between the results of the pretest and posttest. Conclusions: The conclusion is improvements and revisions are still needed. Based on students' perceptions, the GraFIS application met usability and mobile quality standards.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42714955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Periodico Tche QuimicaPub Date : 2021-07-28DOI: 10.52571/ptq.v18.n38.2021.16_peregudov_pgs_224_241.pdf
Y. Peregudov, E. Gorbunova, Behzod Aminovich Obidov, Ks Kim, S. I. Niftaliev
{"title":"STUDY OF THE SORPTION OF AMMONIUM CATIONS ON A FIBROUS CARBOXYLIC SORBENT","authors":"Y. Peregudov, E. Gorbunova, Behzod Aminovich Obidov, Ks Kim, S. I. Niftaliev","doi":"10.52571/ptq.v18.n38.2021.16_peregudov_pgs_224_241.pdf","DOIUrl":"https://doi.org/10.52571/ptq.v18.n38.2021.16_peregudov_pgs_224_241.pdf","url":null,"abstract":"Background: Wastewater from the mineral fertilizer production, agribusiness containing ammonium ions causes significant harm to fish farming; therefore, it must be purified before discharge. Ion-exchange sorption is a promising method for isolating ammonium cations. The object of the study was a chemisorption fiber VION KN-1, which has developed surface and high sorption rate. Purpose: To study the sorption kinetics of ammonium cations from aqueous solutions on VION KN-1; to train an ANN to predict the degree of recovery of ammonium ions from wastewater using Statistica Neural Networks Version 13. Methods: The ammonium ion concentration in the solution was established by direct potentiometry. Sorption isotherms were constructed using the method of variable concentrations. To determine the limiting stage, the obtained kinetic dependencies were represented in the coordinates of the Boyd-Adamson equations for internal/external diffusion. Results and Discussion: During sorption from solutions with different ammonium nitrogen contents, the values of distribution coefficients (Kd) are at the level of 2.3ꞏ103 cm3/g, which significantly exceeds this parameter for granular ionites. Experimental sorption data were verified using Freundlich (R2 = 0.9224) and Langmuir (R2 = 0.9996) isotherms. The maximum degree of recovery (over 96 %) was achieved by passing a solution with a concentration of 11.3 mmol/dm3. Using an array of experimental data, the MLP-3-5-1 neural network was trained. The coefficient of determination R2 = 0.999420 obtained for the training sample characterizes high network performance. Conclusions: The Langmuir equation better describes the process of NH4+ sorption on a fibrous sorbent. It is reasonable to use VION KN-1 at the fine treatment stage. Ammonium ion desorption from the fiber was performed by acid solution. The resulting solutions of ammonium salts can be used as liquid fertilizers. The trained neural networks can be used to predict the degree of recovery of ammonium ions by sorbent VION KN-1.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42629153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Periodico Tche QuimicaPub Date : 2021-06-25DOI: 10.52571/ptq.v18.n38.2021.15_atolani_pgs_214_223.pdf
O. Atolani, O. Olorundare, Priyanka Banerjee, O. Adeyemi, R. Preissner
{"title":"ISOLATION, CHARACTERIZATIONS, ANTI-CANCER, CYTOTOXICITY, IN SILICO TOXICITY, AND ANTIMICROBIAL EVALUATIONS OF MORINGA OLEIFERA SEED PROTEIN","authors":"O. Atolani, O. Olorundare, Priyanka Banerjee, O. Adeyemi, R. Preissner","doi":"10.52571/ptq.v18.n38.2021.15_atolani_pgs_214_223.pdf","DOIUrl":"https://doi.org/10.52571/ptq.v18.n38.2021.15_atolani_pgs_214_223.pdf","url":null,"abstract":"Background: Moringa oleifera seed, which is widely utilized as an affordable source of domestic water treatment, is also reputable for its various pharmacological applications globally. Aim: This study evaluates the toxicity and pharmacological potentials of Moringa oleifera seed protein while establishing the chemical profile. Method: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and liquid chromatography coupled with electrospray ionization mass spectrometry (LC-ESI-MS/MS) were used to analyze the protein/peptide content of the purified protein. The protein was also investigated for in vitro anticancer potential on Hela and MDA-MB-231 cell lines, cytotoxic on 3T3 cell line, and toxicity to brine shrimps. In addition, the antimicrobial action of the protein (polypeptide) was evaluated. Results and Discussion: The MALDI-MS revealed three protein moieties with values of 3.4, 4.6, and 6.9 kDa. On the other hand, LC-ESIMS/MS analysis revealed dipeptides and tripeptides, which include serinylarginine, leucylproline, leucylmethionyl-glycine, isoleucyl-glycyl-methinine, glycyl-arginyl-aspartic acid, isoleucyl-glutamyl-methionine, diphenylalanine, asparaginyl-aspartyl-histidine, seryl-tyrosyl-tyrosine, phenylalanyl-asparaginyl-tyrosine, and propanolyl-trytophanyl-glycine. The seed protein exhibited extremely low toxicity on both 3T3 and MDA-MB-231 breast cancer cell lines, while the standards, doxorubicin, and cycloheximide had IC50 = 0.5 ± 0.07 and 0.8 ± 0.10 μg/mL, respectively. Further, the protein showed no antibacterial or antifungal activity against all tested organisms. The protein also exhibited no lethality against brine shrimp. The in-silico toxicity results indicated that the peptides are not immunotoxic, carcinogenic, or mutagenic as most belonged to the tox class V except serylarginine predicted for tox class IV (harmful if swallowed). Hence, the intake of the protein remnant in water could be within the tolerable limit. Conclusion: The results obtained suggested that the protein content of the Moringa oleifera seed is non-cytotoxic. The result further validates the safety potential of the defatted and debittered seed material used as potential food sources for both humans and animals.","PeriodicalId":45103,"journal":{"name":"Periodico Tche Quimica","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41932750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}