scholarly journals Comparative Analysis of Selected Physicochemical Properties of Pozzolan Portland and MTA-Based Cements

2014 ◽  
Vol 2014 ◽  
pp. 1-7
Author(s):  
Maura Cristiane Gonçales Orçati Dorileo ◽  
Ricardo Dalla Villa ◽  
Orlando Aguirre Guedes ◽  
Andreza Maria Fábio Aranha ◽  
Alex Semenoff-Segundo ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Comparative Analysis ◽  
Portland Cement ◽  
Physicochemical Properties ◽  
American National Standard Institute ◽  
Statistical Analyses ◽  
National Standard ◽  
Distilled Water ◽  
Mean Values ◽  
Level Of Significance

Physicochemical properties of pozzolan Portland cement were compared to ProRoot MTA and MTA BIO. To test the pH, the samples were immersed in distilled water for different periods of time. After the pH analysis, the sample was retained in the plastic recipient, and the electrical conductivity of the solution was measured. The solubility and radiopacity properties were evaluated according to specification 57 of the American National Standard Institute/American Dental Association (ANSI/ADA). The statistical analyses were performed using ANOVA and Tukey’s test at a 5% level of significance. Pozzolan Portland cement exhibited pH and electrical conductivity mean values similar to those of the MTA-based cements. The solubilities of all tested materials were in accordance with the ANSI/ADA standards. Only the MTA-based cements met the ANSI/ADA recommendations for radiopacity. It might be concluded that the pH and electrical conductivity of pozzolan Portland cement are similar to and comparable to those of MTA-based cements.

scholarly journals Analysis of Ground Water from Selected Sources in Jalingo Metropolis, Nigeria

2021 ◽  
Author(s):  
Benjamin Ezekeil Bwadi ◽  
Mohammed Bakoji Yusuf ◽  
Ibrahim Abdullahi ◽  
Clement Yakubu Giwa ◽  
Grace Audu
Keyword(s):  
Electrical Conductivity ◽  
Drinking Water ◽  
Dissolved Oxygen ◽  
Physicochemical Properties ◽  
Ground Water ◽  
Waste Disposal ◽  
Chemical Properties ◽  
Total Dissolved Solids ◽  
Dissolved Solids ◽  
Mean Values

Water is very significant in the development of a stable community, but many societies are confronted with the challenges of poor wastes management system with indiscriminate waste disposal and bad land practices, which easily pollute water sources and consequently degrade water quality. This study was to analyze the physicochemical properties of ground water from multiple point sources in Jalingo, Taraba state of Nigeria. Water samples were collected from twenty seven (27) sites from the study area during the raining and dry seasons. The analysis was carried out to determining the physico-chemical properties of the ground water and comparing with the World Health Organization (WHO) standard for drinking water. The physicochemical properties of ground water analyzed include; odor, taste, temperature and electrical conductivity were tested in the field using water meter tester. Whereas pH, total dissolved solids, alkalinity, hardness, salinity, iron, manganese, fluoride, nitrate, nitrite, chloride, sulphate and dissolved oxygen were analyzed in the laboratory using Wagtech potable water testing equipment. The physical properties of water analyzed were temperature, odor, taste, and turbidity. Whereas the chemical properties of water analyzed were pH, electrical conductivity (EC), total dissolved solids (TDS), alkalinity, hardness, salinity, iron (Fe), manganese (Mn), fluoride (F−), nitrate (NO3−), nitrite (NO2−), Chloride (Cl−), sulphate (SO42−), dissolved oxygen (DO).The result shows the range of the mean values of the temperature(26.7–33.1) oC, p H(6.5–8.9), Fe (0.01–0.08 mg/L), NO3−(0.01–38.5 mg/l), NO2−(0.01–0.09 mg/l), Mn (0.01–0.17 mg/l), F(0.01–0.82 mg/l), alkalinity(39-204 mg/l), salinity (42-508 mg/l), SO4(14-93 mg/l), total dissolved solids (6–637) mg/l, turbidity(0.4–10.6 mg/l), hardness(48-187 mg/l), and fecal coliforms(1–4)fcu/100mi, dissolved oxygen(1.1–6.87)mg/l, EC(10.99–1066)ohm/cm, Cl (10-320 mg/l). All except alkalinity and hardness are within the WHO permissible standards of quality drinking water. The highest alkalinity (204 mg/l), hardness (187 mg/l) and low dissolved oxygen (6.87 mg/l) attributed to the high concentration of dissolved salts and basic cations in the water. The methodology applied in the study was effective in analyzing the physicochemical properties of water in the study area. Therefore, it was recommended that there should be frequent water source testing by stakeholder in water resources with the view to treating the water. Policy maker should also enforce the regulation of the use of chemical fertilizers, agro-chemicals and the indiscriminate waste disposal.

scholarly journals Physicochemical Properties and Surfaces Morphologies Evaluation of MTA FillApex and AH Plus

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Álvaro Henrique Borges ◽  
Maura Cristiane Gonçales Orçati Dorileo ◽  
Ricardo Dalla Villa ◽  
Alexandre Meireles Borba ◽  
Tereza Aparecida Delle Vedove Semenoff ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Conductivity Measurement ◽  
Mean Value ◽  
Electrical Conductivity Measurement ◽  
Homogeneous Surface ◽  
Mean Values ◽  
Wide Range ◽  
Significant Difference ◽  
Ah Plus ◽  
Level Of Significance

The solubility, pH, electrical conductivity, and radiopacity of AH Plus and MTA FillApex were evaluated. In addition, the surfaces morphologies of the sealers were analyzed by using scanning electron microscopy. For pH test, the samples were immersed in distilled water at different periods of time. The same solution was used for electrical conductivity measurement. The solubility and radiopacity were evaluated according to ANSI/ADA. Statistical analyses were carried out at 5% level of significance. MTA FillApex presented higher mean value for solubility and electrical conductivity. No significant difference was observed in the mean values for pH reading. AH Plus presented higher radiopacity mean values. MTA FillApex presented an external surface with porosities and a wide range of sizes. In conclusion, the materials fulfill the ANSI/ADA requirements when considering the radiopacity and solubility. AH Plus revealed a compact and homogeneous surface with more regular aspects and equal particle sizes.

scholarly journals EFINITION OF DEFORMATION OF FINE-GRAINED CONCRETE ON THE BASIS OF SULPHATE-RESISTANT PORTLAND CEMENT

Vestnik MGSU ◽  
2018 ◽  
pp. 1499-1508
Author(s):  
Ngo Xuan Hung ◽  
Tang Van Lam ◽  
Boris I. Bulgakov ◽  
Olga V. Aleksandrova ◽  
Oksana A. Larsen
Keyword(s):  
Portland Cement ◽  
Raw Materials ◽  
Setting Time ◽  
Relative Increase ◽  
Relative Deformation ◽  
Fine Aggregate ◽  
Distilled Water ◽  
Mean Values ◽  
Sand Mixture ◽  
Fine Grained

Introduction. The possibility of determining the relative deformations of fine-grained concretes based on sulfate-resistant cement was formulated by testing samples of gypsum-cement-sand mixture in distilled water in accordance with the requirements of the Vietnamese standard TCVN 6068:2004. Objective - to determine the deformations of fine-grained concrete because of sulfate-resistant Portland cement in accordance with the requirements of the TCVN 6068:2004 standard to assess its resistance to corrosion in an aggressive sulfate medium. Materials and methods. To obtain a gypsum-cement-sand mixture, a finely disintegrating binder was used, consisting of sulfate-resistant Portland cement of the type CEM I CC 42.5 N produced by the “Tam Diep” plant with the addition of natural gypsum produced by the company “Dinh Vu”. Quartz sand was used as fine aggregate. All raw materials used were native to Vietnam. Grinding fineness, normal cement density, setting time, the uniformity of the volume change and the activity of sulfate-resistant Portland cement were determined according to GOST 30744-2001; deformations of samples from gypsum-cement-sand mixtures - according to the Vietnamese standard TCVN 6068:2004. Results. Investigated the relative increase in the volume of samples of gypsum-cement-sand mixture based on sulfate-resistant Portland cement and natural gypsum as a result of their testing in distilled water according to the standard TCVN 6068:2004. Conclusions. Found that the average value of the relative deformation of the prism samples of concrete as a result of a 14-day test in distilled water was 0.037 %, which is within the acceptable value of 0.04 % in accordance with the requirements of the Vietnamese standard TCVN 6067:2004. Therefore, sulfate-resistant Portland cement type CEM I CC 42.5 N produced by the “Tam Diep” plant is a promising material as a binder for the preparation of corrosion-resistant concrete. The increase in the mean values of the relative deformations of the gypsum-cement-sand prism specimens after the 28-day and 60-day of testing, compared to the results of the 14-day test, can be explained by a slightly increased content of tricalcium aluminate in the studied cement.

Recommendations for Test Lab Regarding Transition to New Requirements GOST ISO/IEC 17025–2019

2020 ◽  
Vol 86 (2) ◽  
pp. 69-78
Author(s):  
S. N. Gusarova ◽  
Yu. M. Erokhina ◽  
D. I. Kramok ◽  
E. I. Khunuzidi
Keyword(s):  
Comparative Analysis ◽  
Russian Federation ◽  
Transition Period ◽  
Process Approach ◽  
National Standard ◽  
The Novel ◽  
Self Assessment ◽  
Testing Laboratories ◽  
The Russian Federation ◽  
Practical Level

Since September 1, 2019, GOST ISO/IEC 17025–2019 has been enacted as a national standard in the Russian Federation. The novel standard imposes a number of fundamentally new requirements for testing laboratories (hereinafter referred to as the IL or laboratory), and also supplements and specifies the requirements previously regulated by GOST ISO/IEC 17025–2009. In this regard, in order to transfer laboratories to the new requirements, the FSA issued an order in August 2019 listing the mandatory activities that IL must fulfill to bring their activities in line with the new requirements. However, a transition period desired for matching these requirements is absent on a practical level for a number of the laboratories. The purpose of the article is to facilitate a gentle, efficient and pain-free move from the requirements of GOST ISO/IEC 17025–2009 to the new requirements of GOST ISO/IEC 17025–2019, including compliance with new changes in accreditation criteria. We carried out a comparative analysis of the requirements of the new and previous versions of the standard and marked each new and significant item to which the laboratory should pay attention first of all. The new standard focuses on the application of the process approach, risk and opportunity management, as well as on implementation of the policy of impartiality, independence, minimization of competitive interests and confidentiality. The article describes the planning, implementation and monitoring of each event or phase of the transition of testing laboratories to new requirements. Moreover, the recommendations on the structure of the «Quality Manual» and self-assessment on the compliance of IL activities and QMS with the new requirements, including the use of statistical methods for substantiation of the correctness of the assessment are given as an example of the implementation of IL capabilities.

scholarly journals SIFAT FISIKOKIMIA HAND AND BODY CREAM DENGAN PEMANFAATAN EKSTRAK ETANOL BUNGA GEMITIR (Tagetes erecta L.) DAN BUNGA PACAR AIR MERAH (Impatiens balsamina L.) DARI LIMBAH CANANG

2017 ◽  
Vol 5 (1) ◽  
pp. 1
Author(s):  
Dewa Ayu Ika Paramitha ◽  
James Sibarani ◽  
Ni Made Suaniti
Keyword(s):  
Antioxidant Activity ◽  
Physicochemical Properties ◽  
National Standard ◽  
Tagetes Erecta ◽  
Basic Formula ◽  
Impatiens Balsamina ◽  
Ethanol Extracts ◽  
Tagetes Erecta L ◽  
Microbial Numbers

ABSTRAK: Pada penelitian ini dilakukan pengembangan formula sediaan hand and body cream dengan memanfaatkan sumber antioksidan yang dimiliki oleh dua jenis ekstrak etanol yaitu ekstrak bunga pacar air merah (Impatiens balsamina L.) dan bunga gemitir (Tagetes erecta L.) dengan taraf perlakuan sebesar 1% dari masing-masing ekstrak (FPM dan FG) dan campuran 0,5% ekstrak pacar air merah dan 0,5% ekstrak gemitir (FCPMG). Pengujian terhadap  produk dilakukan pada sifat fisikokimia  meliputi pH, viskositas, aktivitas antioksidan, angka lempeng total mikroba, dan ukuran partikel. Berdasarkan hasil pengujian produk hand and body cream yang dihasilkan memiliki antioksidan yang cukup tinggi sebagai produk perawatan tubuh dengan penambahan 1% ekstrak etanol pacar air merah, gemitir dan campuran dari kedua ekstrak etanol. Kualitas produk hand and body cream yang dihasilkan baik dan memenuhi standar mutu SNI dari aspek nilai pH, viskositas, dan nilai ALT. Warna yang dihasilkan mulai dari warna kuning kemerahan sampai dengan warna kuning, dan partikel yang dimiliki oleh produk adalah nanopartikel dengan sistem polidispersi. ABSTRACT: Formulations of hand and body creams using ethanol extracts of flowers of red Impatiens balsamina L. And Tagetes erecta L. As antioxidant sources have been developed.  One percent of  extracts (FPM and FG) and the mixture of 0.5% each extracts (FCPMG) were added to the basic formula. The analysis of physicochemical properties of the products was conducted including pH, viscosity, antioxidant activity, the size of the particles, and total microbial plate numbers. Based on the results, the quality of the hand and body creams meet the national standard of Indonesia (SNI) regarding to pH, viscosity, and the total microbial numbers. The colours of the hand and body creams resulted are reddish yellow to yellow with polydispersion nanoparticles.

COMPARATIVE ANALYSIS OF CLINICAL EFFICIENCY OF THE DRUG “BIO-DENT” IN BIOLOGICAL METHODS OF TREATMENT OF PULPITES BY THE METHOD OF INDIRECT COATING

2021 ◽  
Vol Special issue (1) ◽  
pp. 51-56
Author(s):  
Nigora Djuraeva ◽  
Keyword(s):  
Comparative Analysis ◽  
Portland Cement ◽  
Calcium Hydroxide ◽  
Dental Pulp ◽  
Mineral Trioxide Aggregate ◽  
Clinical Efficiency ◽  
Near Term ◽  
Biological Methods ◽  
Methods Of Treatment

The article presents the results of using a material based on the mineral trioxide unit “Bio-Dent”for the indirect coating of the pulp. It was found that there were no complaints from the use of domestic Portland cement both in the near term (98.8%) and inthe long term after treatment in comparison with materials based on calcium hydroxide (72.5%). Stabilization of the pulp electroexcitability indicators at the level of 10 mkA was noted with the use of the material based on MTA “Bio-Dent”as a medical liner for indirect pulp covering.Keywords: dental pulp,indirect pulp coating, calcium hydroxide, mineral trioxide aggregate, pulp electroexcitability.

scholarly journals A CONTRIBUTION TO THE HYDROCHEMISTRY AND WATER TYPOLOGY OF THE AMAZON RIVER AND ITS TRIBUTARIES

2019 ◽  
Vol 20 (72) ◽  
pp. 360-374 ◽  
Author(s):  
Maria do Socorro Rocha da Silva ◽  
Eduardo Antonio Ríos-Villamizar ◽  
Hillândia Brandão da Cunha ◽  
Sebastião Átila Fonseca Miranda ◽  
Sávio José Filgueiras Ferreira ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Physicochemical Properties ◽  
Amazon Basin ◽  
The Other ◽  
Amazon River ◽  
Left Bank ◽  
Guiana Shield ◽  
Ionic Charge ◽  
Physical Chemical ◽  
Geological Diversity

The geological diversity of the Amazon Basin, as well as the pluvial regime, influences the characteristics of the waters. To know the water types of the rivers of the Amazon basin, 288 superficial water samples were collected, 94 of them along the Amazon River and 194 in their tributaries, from March 2009 to September 2012. The physical, chemical, and physicochemical properties were analyzed. Rivers with pH between 6.5 and 7.6 and electrical conductivity (40.00 - 80.00 μS cm-1) are water bodies that are influenced by the Andean region (e.g., the Amazon River and some of its right bank tributaries). On the other hand, the rivers with pH in the range of 3.5 to 5.5 and conductivity <30.00 μS cm-1, which are Amazon River’s left bank tributaries, reflect the characteristics of the Guiana Shield. The rivers with pH (6.0 to 7.0), low ionic charge, and conductivity <40.0 μS cm-1, such as the lower Amazon River’s right bank tributaries (Tapajos and Xingu) which are influenced by the Central Brazilian Shield, and also the middle/upper Amazon River’s right bank tributaries (Tefé, Coari and Jutaí).

scholarly journals Pengaruh Lokasi Geografis dan Vegetasi terhadap Sifat Fisikokimia Madu dari Ciwidey dan Bogor

2020 ◽  
Vol 1 (2) ◽  
pp. 71
Author(s):  
Emanuela Rae Alodia ◽  
Anas Bunyamin ◽  
Efri Mardawati
Keyword(s):  
Physicochemical Properties ◽  
Water Content ◽  
Sugar Content ◽  
Geographical Location ◽  
B Value ◽  
Reducing Sugar ◽  
National Standard ◽  
Color Analysis ◽  
A Value ◽  
C Value

<p><em>Physicochemical properties are one of the parameters of honey quality that impacts the sales of honey as well as the economy condition of the society in Ciwidey and Bogor. The physicochemical properties of honey are significantly influenced by the origin of the honey, including its geographical location and vegetation. This study aims to determine the physicochemical properties between multiflora honey from Ciwidey and Bogor with different source of nectar where Ciwidey honey is dominated by calliandra nectar while Bogor honey is dominated by kapok nectar. Data were analyzed with descriptive and quantitative method using independent t test for data with normal distribution (water content and reducing sugar content). Data that were not normally distributed (color analysis and acidity value) were tested non-parametrically with the Mann Whitney-U. The results showed that Bogor honey has the better physicochemical properties and meets Indonesian National Standard (Standar Nasional Indonesia, SNI) 8664:2018, with a water content of 15.15% w/w, L* values of 35.26, a* value of 28.66, b* value of 59.46, c* value of 66.01, h* value of 64.27°, reducing sugar content of 78.78% and acidity value of 35.56 mL NaOH kg-1. Phytochemical screening showed positive results on alkaloid, flavonoid, phenol and tannin, and the results of GC-MS analysis showed three significant compounds which are hydroxymethylfurfural of 48.26%, levoglucosan of 13.58% and ammonium carbamate of 9.18%.</em></p>

scholarly journals EXPERIENCE OF ICT IMPLEMENTATION IN PRIMARY CURRICULUM IN UKRAINE AND THE UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND

2020 ◽  
Vol 75 (1) ◽  
pp. 42-55
Author(s):  
Ірина Василівна Борисенко ◽  
Оксана Павлівна Биконя ◽  
Ольга Олександрівна Рембач ◽  
Лариса Петрівна Шумна ◽  
Олександр Іванович Олійник ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Computer Science ◽  
Primary Education ◽  
Digital Literacy ◽  
Primary Schools ◽  
National Standards ◽  
European Countries ◽  
National Standard ◽  
Advantages And Disadvantages ◽  
Ict Implementation

The study was formulated within the context of an increasing recognition of ICT as curriculum priorities in primary schools of many European countries. The implementation of ICT-centered curriculum is a step towards realizing the goals of the new Law of Ukraine “On Education” (2017), National Strategy for the Development of Education in Ukraine until 2021, European strategic programme “Education and Training 2020”. Actuality of approaches to ICT implementation in present-day primary schools is caused by the substantial development of digital technologies and requirement of digital literacy for people’s work, social, and personal lives. The unique opportunity of primary education as a large sub-sector of any education system is to contribute to the renewal of societies through education of the young. The paper aims to study implementation of Computer science into national standard of primary education in Ukraine and the UK. In the recent years, many European countries have seen some changes of the content one of which relates to the area of computer science education that resulted in implementing an ambitious new curriculum in this subject. The author gives a comparative analysis of primary ICT within national standards in term of the Computer science development from the initial stage to present day situation. The comparative analysis specifies areas of similarities (aims, objectives, approaches to implementation, priorities of developing digital skills, teaching hours) and differences (programme topics, characterization of learning outcomes) in the study of ICT covering the subject content, expected learning results and general principles of ICT in education, as well as examples of ICT implementation. The paper is also focused at discussing the role of the ICT curriculum in modern-day primary classroom; advantages and disadvantages of ICT integration at primary stage. Much attention is paid to how it is integrated into daily learning modes to allow and encourage active learning. In primary education there are two main models of ICT implementation into curriculum, these are: ICT integrated across the curriculum; ICT (or Informatics, Computer Science and Computing) as a discrete subject within national standard.

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