The Adsorption of Superplasticizers on Cement Particles and its Relation with Dispersibility

2013 ◽  
Vol 687 ◽  
pp. 449-455
Author(s):  
Zi Ming Wang ◽  
Ya Li Wang ◽  
Ming Zhang Lan
Keyword(s):  
Zeta Potential ◽  
Cement Paste ◽  
Isoelectric Point ◽  
Test Results ◽  
Cement Pastes ◽  
Adsorption Behaviors ◽  
Adsorption Amount ◽  
The Relationship

The dispersing effect of superplasticizer is closely related to its adsorption behaviors on the surface of cement particles or the hydrates. But the relationship between the adsorption amount of superplasticizer and the fluidity of cement paste seems uncertain. To investigate the relationship between the adsorption amount and the fluidity of cement paste, three groups of cements with designed compositions and C3A mineral were prepared in lab. Four types of superplasticizer were used to measure the adsorption on various cements. The corresponding zeta potential of cement particles with superplasticzers and the fluidity of cement pastes were tested and analyzed. It was found that the adsorption amount of superplasticizer was inversely related to the fluidity of cement paste for a given superplasticizer. The zeta potential of cement particles in the paste was proportional to the adsorption amount of superplasticizer. The adsorption amount of different superplasticizers at the isoelectric point in C3A-H2O system was determined. The meaning of the “adsorption amount” was discussed. The author proposed that the superplasticizer in cement paste should include three parts, and the role of each part was discussed according to test results and analysis.

Properties of Permeable Concrete Substrate Having Dual Pore Structures

2008 ◽  
Vol 569 ◽  
pp. 233-236
Author(s):  
Z. X. Yang ◽  
Kyu Hong Hwang ◽  
Jeong Bae Yoon ◽  
J.O. Kim ◽  
M.C. Kim
Keyword(s):  
Sodium Bicarbonate ◽  
Physical Properties ◽  
Cement Paste ◽  
Water Permeability ◽  
Vacuum Pressure ◽  
Adsorption Ability ◽  
Cement Pastes ◽  
Porous Concrete ◽  
Digital Microscope

Porous concretes with continuous voids have been gaining more interest as an ecological material because of their useful functions such as water permeability and adsorption ability. Especially, to make porous concrete much more environmentalized, micropores play a role of nest for microorganism and germs to live in. So micropore distribution and the size of micropores especially open pores are the key point . In this study, the size and distribution of micropores of porous concrete were effected by the AE agents to the cement pastes and then by the treating types, treating times, treating temperatures, and the vacuum pressure during the treating. And another group specimens were added sodium bicarbonate and alum. And then physical properties were examined, digital microscope was also used to observe the micropores sizes and distributions. Cracks were observed on the cement-aggregate joint when the amount and vacuum pressure increased. And high treating temperature shows no good on the bonding of cement paste and aggregate.

Influences of Superplasticizer on the Interaction between Latex Particles and Cement Grains

2013 ◽  
Vol 687 ◽  
pp. 335-340 ◽  
Author(s):  
Dong Dong Han ◽  
Jin Mei Li ◽  
Wei Deng Chen ◽  
Shi Yun Zhong
Keyword(s):  
Zeta Potential ◽  
Cement Paste ◽  
Adsorption Rate ◽  
Test Results ◽  
Polymer Particles ◽  
Latex Particles

In order to have a better understand on the interaction among superplasticizer, latex and cement grains in the fresh cement paste, the zeta potential and the adsorption of polymer on the cement were investigated in this study. The zeta potential was measured by using the ZetaProbe instrument, and the adsorption rate of latex was analyzed by sedimentation test. The zeta potential results show that the zeta potential of pure cement paste is positive and increasing slightly along the first 30mins; the latex particles can be adsorbed by cement grains, comparing with SAE latex, the adsorption of PAE latex is lower, and PAE latex has a smaller influence on the hydration of cement paste; the presence of superplasticizer can affect the adsorption of polymer particles on the cement; the sedimentation test results show that the presence of PC and NF can reduce the adsorption of latex particles, when the dosage of PC is more than 0.3%, the adsorption rate of latex particles is reduced significantly; when the dosage of NF is 1%, the adsorption rate of latexes is reduced less than that in the case of PC.

scholarly journals The role of Campylobacter spp. in chronic enteropathy in dogs

2019 ◽  
Vol 88 (3) ◽  
pp. 341-347
Author(s):  
Miloš Vávra ◽  
Gabriela Bořilová ◽  
Michal Fusek ◽  
Vojtěch Gabriel ◽  
Václav Ceplecha ◽  
...  
Keyword(s):  
Histopathological Examination ◽  
Test Results ◽  
Research Subjects ◽  
Chronic Enteropathy ◽  
Gastrointestinal Problems ◽  
Stool Samples ◽  
Campylobacter Upsaliensis ◽  
The Relationship ◽  
Campylobacter Spp

The aim of the study was to identify Campylobacter species in a group of patients with chronic gastrointestinal problems and to investigate the relationship between the presence of Campylobacter spp. in stool samples and as well as the severity of chronic enteropathy. Twenty-six dogs with chronic gastrointestinal problems were included in the prospective study. Each research subject had their stomach, duodenum, ileum, and colon examined endoscopically. A histopathological examination of the obtained biopsy samples was then performed, excluding other potential diseases. Stool samples were collected and then examined for the presence of Campylobacter spp. To evaluate the relationship between Campylobacter spp. occurrence and the intensity of chronic enteropathy, patients were divided into two groups; animals in the first group presented with no to mild inflammation whereas research subjects in the second group suffered from moderate to severe inflammation. Subsequently, the patients were divided based on positive or negative test results for Campylobacter spp. cultures. No significant relationship between the presence of Campylobacter spp. in stool samples and chronic enteropathy was found. In contrast to other previously published papers, our study showed a lower occurrence of Campylobacter upsaliensis.

scholarly journals Evaluasi Program Pembelajaran Karakter Berbasis Revolusi Mental SMP di Kabupaten Sumbawa

2019 ◽  
Vol 3 (3) ◽  
pp. 51-58
Author(s):  
Roni Hartono ◽  
Yudi Mulyanto
Keyword(s):  
Character Education ◽  
Junior High School ◽  
Research Method ◽  
Evaluation Model ◽  
Research Data ◽  
Test Results ◽  
Education Data ◽  
Role Of Religion ◽  
The Relationship

The purpose of this research is to: see the extent of the role of religion and the role of the environment in character education in junior high school in Sumbawa district. The research method used is evaluation model using the correlation analysis of both religions and the environment. Research Data is obtained from religious instruments and the environment whose validity is proven using the validity and validity of factors with EFA (Exploratory Factor Analysis). The results of the study show environmental-based character education data is 3.64 which means the education of environmental based character is in good category. The result of the data analysis of religious-based character education instruments is 3.24 which means the education of environmental based character is in good category. The correlation test results between the two variables are positively valued with a correlation value of 0.221 with a sig. (p count) = 0.0001 or P < 0.05 which means the relationship that occurs between the two variables is significant.  

Study on Dispersion Properties of an Amphoteric Polycarboxylate Superplasticizer on Cement Pastes

2012 ◽  
Vol 502 ◽  
pp. 208-211 ◽  
Author(s):  
Qiang Cao ◽  
Sheng Hua Lv ◽  
Di Li
Keyword(s):  
Polyethylene Glycol ◽  
Acrylic Acid ◽  
Zeta Potential ◽  
Synergistic Effects ◽  
Molar Ratio ◽  
Steric Repulsion ◽  
Cement Pastes ◽  
Polycarboxylate Superplasticizer ◽  
Cationic Monomer ◽  
Adsorption Amount

A novel amphoteric polycarboxylate superplasticizer (APCs) was prepared by solution copolymerization from acrylic acid (AA), allyl polyethylene glycol (APEG), diallyldimethyl ammonium chloride (DMDAAC). Effects of DMDAAC dosage and monomers ratio on performance of APCs were investigated by tested of zeta potential of cement particles and adsorption on cement. Results indicated that introducing of cationic monomer can increase the saturation adsorption amount and dispersibility of APCS. When the molar ratio of AA and APEG and DMDAAC is 5:1:0.5, the dispersibility of APcs has the best adsorptivity and disersibility. The synergistic effects of Zeta potential and steric repulsion of the cement particles surface is the main mechanism for dispersion.

scholarly journals Adaptation of the Relationship and Motivation Scale to the Turkish Culture

2017 ◽  
Vol 6 (3) ◽  
pp. 181
Author(s):  
Munevver Ilgun Dibek ◽  
Hatice C Yavuz ◽  
Ezel Tavsancil ◽  
Seher Yalcin
Keyword(s):  
Factor Analysis ◽  
Cultural Comparison ◽  
Test Results ◽  
Cross Cultural Comparison ◽  
Explanatory Factor Analysis ◽  
Confirmatory Factor ◽  
Turkish Culture ◽  
Using Data ◽  
The Relationship

The purpose of the present study was twofold: first to adapt the Relationship and Motivation (REMO) scale addressing role of peers and teachers in students’ motivations into Turkish culture, and second to determine whether there were any differences between girls and boys regarding the scores obtained from this scale. To achieve these aims, the present research was designed to be comprised of three consecutive studies. In Study 1, linguistic equivalence was established, and results of an Explanatory Factor Analysis (EFA) performed on data obtained from 202 students showed that structure of the original scale was supported. In Study 2, a Confirmatory Factor Analysis (CFA) was conducted using data obtained from 496 Turkish students, and the results confirmed the results of EFA. Additionally, the validity evidence was obtained by conducting another EFA with 528 students. Moreover, reliability coefficients were also found to be varying in an acceptable range. Including the same participants of Study 2 in Study 3, t-test results showed that girls had significantly higher mean scores on the subscales of peers and teachers as positive motivators, and teachers as negative motivators. On the other hand, boys had significantly higher mean scores on the scale of peers as negative motivators. Results of these studies suggest that Turkish version of REMO is conceptually equivalent to original REMO, and similarly reliable and valid. Therefore, the adapted scale can not only be used in cross-cultural comparison and but also for determining the differentiation in the relations of students with their peers and teachers.

scholarly journals The view of a general practitioner on immediate access for patients to their laboratory test results

2018 ◽  
Vol 57 (3) ◽  
pp. 375-382
Author(s):  
Syed Ghulam Sarwar Shah ◽  
Amir Hannan ◽  
Bruce Elliott ◽  
Ingrid Brindle ◽  
Richard Fitton
Keyword(s):  
General Practice ◽  
General Practitioner ◽  
Laboratory Test ◽  
Text Messages ◽  
Test Results ◽  
Traditional Practice ◽  
Online Tools ◽  
Laboratory Test Results ◽  
The Relationship

Abstract This position paper presents the role of laboratory test results in traditional general practice and provides a recommendation for responsible sharing of results with patients for improved safety, efficiency and outcomes. This paper looks at the relationship between the laboratory, the general practitioner consultation, the patient, safety and general practice capacity. We suggest changes in the traditional practice of communicating laboratory test results whereby normal or abnormal results are made available to patients as soon as they become available. We also endorse the opinion that using online tools such as email or text messages could enhance the provision of rapid access to laboratory test results for patients.

scholarly journals Implementation of Quintuple Helix in the Development and Improvement of SMEs Competitiveness in Banyuwangi Regency

2021 ◽  
Vol 3 (1) ◽  
pp. 232-241
Author(s):  
Herdiana Dyah Susanti ◽  
Dian Arief Pradana
Keyword(s):  
Civil Society ◽  
Experimental Research ◽  
Natural Environment ◽  
Test Results ◽  
Quintuple Helix ◽  
Post Test ◽  
The University ◽  
The Relationship ◽  
University Industry

Innovation is an interactive result that involves various types of actors based on the helix concept where each actor contributes according to its role. University, Industry, Government, Civil Society and media and culture-based society, society and natural environment in the concept of quintuple helix. This study aims to (1) Demonstrate the relationship between quintuple helix in developing SMEs competitiveness, (2) Effectiveness of the application of quintuple helix in developing SMEs competitiveness. This research is almost the same as experimental research with the pre-test - post-test results of the application of quintuple helix at SMEs in Banyuwangi Regency. The results of this study show the role of the University, Industry, Government, Civil Society as well as media and culture-based society, society and the natural environment in the concept of quintuple helix can improve the competitiveness of SMEs, enhance the capabilities of HR, improve the quality, and competitiveness of products produced by SMEs.

Role of Antiplatelet/Anticoagulant Medications and Blood-Clotting Tests in Prediction of Traumatic Foot Compartment Syndrome

2018 ◽  
Vol 39 (6) ◽  
pp. 725-730
Author(s):  
Young Hwan Park ◽  
Won Seok Choi ◽  
Gi Won Choi ◽  
Hak Jun Kim
Keyword(s):  
Regression Analysis ◽  
Compartment Syndrome ◽  
Blood Clotting ◽  
Test Results ◽  
Medication History ◽  
Level Of Evidence ◽  
Antiplatelet Medication ◽  
Foot Injury ◽  
The Relationship

Background: Although intracompartmental bleeding is one cause of traumatic compartment syndrome, no previous studies have defined the role of hemostatic stability in the development of traumatic compartment syndrome. Therefore, to investigate this issue, we identified the relationship between antiplatelet/anticoagulant medications and the development of traumatic foot compartment syndrome. In addition, as a possible predictor of compartment syndrome, we evaluated the utility of blood-clotting tests in the prediction of traumatic foot compartment syndrome. Methods: Retrospective review of patients diagnosed with isolated foot injury in our institution between 2008 and 2016 was used to identify patients who had traumatic foot compartment syndrome. Potential predictors, including medication history for antiplatelet/anticoagulant agents and blood-clotting test results, were analyzed using logistic regression analysis. The present study included 789 feet, and 29 (3.7%) had traumatic foot compartment syndrome. Results: The antiplatelet medication and the blood-clotting test results were not significantly associated with the development of traumatic foot compartment syndrome. Among other variables, damage caused by heavy objects as the injury mechanism was the only significant predictor in the development of traumatic foot compartment syndrome ( P < .05). Conclusion: Our results showed that antiplatelet medication and blood-clotting tests did not predict the development of traumatic foot compartment syndrome. Level of Evidence: Level III, retrospective comparative series.

scholarly journals Mathematics, curriculum and assessment: The role of taxonomies in the quest for coherence

Pythagoras ◽  
2014 ◽  
Vol 35 (2) ◽  
Author(s):  
Caroline Long ◽  
Tim Dunne ◽  
Hendrik De Kock
Keyword(s):  
South African ◽  
Teaching And Learning ◽  
Mathematics Curriculum ◽  
Mathematical Concept ◽  
Test Results ◽  
Cognitive Domains ◽  
Cognitive Component ◽  
Routine Procedures ◽  
The Relationship

A challenge encountered when monitoring mathematics teaching and learning at high school is that taxonomies such as Bloom’s, and variations of this work, are not entirely adequate for providing meaningful feedback to teachers beyond very general cognitive categories that are difficult to interpret. Challenges of this nature are also encountered in the setting of examinations, where the requirement is to cover a range of skills and cognitive domains. The contestation as to the cognitive level is inevitable as it is necessary to analyse the relationship between the problem and the learners’ background experience. The challenge in the project described in this article was to find descriptive terms that would be meaningful to teachers. The first attempt at providing explicit feedback was to apply the assessment frameworks that include a content component and a cognitive component, namely knowledge, routine procedures, complex procedures and problem solving, currently used in the South African curriculum documents. The second attempt investigated various taxonomies, including those used in international assessments and in mathematics education research, for constructs that teachers of mathematics might find meaningful. The final outcome of this investigation was to apply the dimensions required to understand a mathematical concept proposed by Usiskin (2012): the skills-algorithm, property-proof, use-application and representation-metaphor dimension. A feature of these dimensions is that they are not hierarchical; rather, within each of the dimensions, the mathematical task may demand recall but may also demand the highest level of creativity. For our purpose, we developed a two-way matrix using Usiskin’s dimensions on one axis and a variation of Bloom’s revised taxonomy on the second axis. Our findings are that this two-way matrix provides an alternative to current taxonomies, is more directly applicable to mathematics and provides the necessary coherence required when reporting test results to classroom teachers. In conclusion we discuss the limitations associated with taxonomies for mathematics.

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