Advanced Early Strength Agent Development and Mechanism Analysis

2011 ◽  
Vol 261-263 ◽  
pp. 323-327 ◽  
Author(s):  
Yun Zhong Shi ◽  
Qi Wang ◽  
Peng Song ◽  
Li Li Jia
Keyword(s):  
Cement Hydration ◽  
Calcium Nitrate ◽  
Xrd Analysis ◽  
Mechanism Analysis ◽  
Mineral Formation ◽  
Early Strength ◽  
Main Components ◽  
Further Development ◽  
Agent Development

Preparation of advanced early strength agent ,the main components including organic A, organic B and calcium nitrate. Then tested advanced early strength agent performance for concrete. Though text, we find, the compressive strength and flexural strength of the specimen, use of the advanced early strength agent is greatly improved than with its much better not to use advanced early strength agent. With the passage of time, advanced early strength agent added does not make the strength of concrete worse, but better.Use SEM and XRD analysis technology text advanced early strength agent by adding performances of concrete, including the degree of cement hydration, the morphology of hydration products and the composition of mineral formation. analysis of the role of advanced early strength agents from the perspective of the mechanism. Identified advanced early strength agent impact on the cement hydration, for the further development of early strength agent to provide a theoretical basis.

Preparation and Mechanism Analysis of High-Efficiency early Strength Agent

2012 ◽  
Vol 535-537 ◽  
pp. 2483-2487 ◽  
Author(s):  
Ming Sheng Zhang
Keyword(s):  
Cement Hydration ◽  
High Efficiency ◽  
Calcium Nitrate ◽  
Xrd Analysis ◽  
Mechanism Analysis ◽  
Hydration Products ◽  
Mineral Formation ◽  
Early Strength ◽  
Further Development

High-efficiency early strength agents were obtained which included triethanolamine, glycol and calcium nitrate. Then it was tested for concrete. Though text, we find that the compressive strength and flexural strength of the specimen, use of the high-efficiency early strength agent is greatly improved than with its much better not to use high-efficiency early strength agent. With time go on, high-efficiency early strength agent added does not make the strength of concrete worse, but better. Using SEM and XRD analysis technology text high-efficiency early strength agent by adding performances of concrete, including the degree of cement hydration, the morphology of hydration products and the composition of mineral formation. Analysis of the role of high-efficiency early strength agents from the perspective of the mechanism. Identified high-efficiency early strength agent impact on the cement hydration, for the further development of early strength agent to provide a theoretical basis.

scholarly journals Evaluation of Mechanical and Shrinkage Behavior of Lowered Temperatures Cementitious Mortars Mixed with Nitrite–Nitrate Based Accelerator

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3686
Author(s):  
Yusuke Tomita ◽  
Akira Yoneyama ◽  
Heesup Choi ◽  
Masumi Inoue ◽  
Jihoon Kim ◽  
...  
Keyword(s):  
Calcium Nitrate ◽  
Frost Damage ◽  
Cold Weather ◽  
Early Age ◽  
Calcium Nitrite ◽  
Concrete Hydration ◽  
Early Strength ◽  
Main Components ◽  
Nitrite Nitrate ◽  
Shrinkage Behavior

Recently, calcium nitrite (Ca(NO2)2) and calcium nitrate (Ca(NO3)2) have been increasingly used as the main components of salt- and alkali-free anti-freezing agents, for promoting concrete hydration in cold-weather concreting. With an increase in the amount of nitrite-based accelerator, the hydration of C3A, C3S, and βC2S in the cement is accelerated, thereby improving its early strength and effectively preventing the initial frost damage. Meanwhile, with an increase in the amount of nitrite-based accelerator, the expansion and shrinkage of the concrete—and, therefore, the crack occurrence—are expected to increase. In this study, various experiments were conducted on shrinkage, crack initiation, and the development of mortar containing a considerable amount of a nitrite-based accelerator. The result confirmed that, as the amount of nitrite-based accelerator was increased, the shrinkage was increased, and cracking in early age was more likely to occur, compared to the cases without the addition of this accelerator.

Cognitive Health Counseling 40+

2013 ◽  
Vol 21 (1) ◽  
pp. 24-33 ◽  
Author(s):  
Anne Eschen ◽  
Franzisca Zehnder ◽  
Mike Martin
Keyword(s):  
Outcome Variable ◽  
Pilot Phase ◽  
Subjective Memory ◽  
Cognitive Health ◽  
Health Counseling ◽  
Agents Of Change ◽  
Main Outcome Variable ◽  
Further Development

This article introduces Cognitive Health Counseling 40+ (CH.CO40+), an individualized intervention that is conceptually based on the orchestration model of quality-of-life management ( Martin & Kliegel, 2010 ) and aims at improving satisfaction with cognitive health in adults aged 40 years and older. We describe the theoretically deduced characteristics of CH.CO40+, its target group, its multifactorial nature, its individualization, the application of subjective and objective measures, the role of participants as agents of change, and the rationale for choosing participants’ satisfaction with their cognitive health as main outcome variable. A pilot phase with 15 middle-aged and six older adults suggests that CH.CO40+ attracts, and may be particularly suitable for, subjective memory complainers. Implications of the pilot data for the further development of the intervention are discussed.

Problems and prospects for the Russian banking supervision development in modern conditions

2020 ◽  
Vol 26 (6) ◽  
pp. 1283-1296
Author(s):  
K.A. Omarieva ◽  
P.G. Isaeva
Keyword(s):  
Banking System ◽  
Main Role ◽  
Banking Supervision ◽  
Monetary System ◽  
The Russian Federation ◽  
Document Flow ◽  
Development Methods ◽  
Further Development ◽  
Development Prospects

Subject. The article addresses problems and prospects for the banking supervision development in the Russian Federation under modern conditions. Objectives. We review the essence and methods of organization of the banking supervision, and identify the main problems and prospects for its development. Methods. To provide valid, reliable and reasoned recommendations, we apply normative and integrated approaches to the study of the banking supervision effectiveness in the current circumstances. Results. The paper investigates main problems and development prospects for the Russian banking supervision. The essential importance of supervision comes from the main role of the banking system in maintaining accounts of economic entities and making settlements. Even minor failures or delays in operations can lead to negative outcomes and disastrous consequences for the entire monetary system and the national economy. Therefore, we highlight issues that require attention, and make proposals for further development of the banking supervision. Conclusions. In the context of dynamically developing economy, the banking practice is becoming more complex. As a result, there is a need for new financial instruments that can reduce risks, increase the speed and efficiency of operations and document flow, and help achieve the world levels of introduced standards.

ANALYSIS OF APPLICATION OF BLOCKCHAIN TECHNOLOGIES FOR THE BANKING SECTOR

2017 ◽  
Author(s):  
Svitlana Ilkovych ◽  
◽  
Maryna Korol ◽  
Keyword(s):  
Banking Sector ◽  
Blockchain Technology ◽  
Current State ◽  
Global Banking ◽  
Banking Institutions ◽  
Pros And Cons ◽  
Further Development

The article considers the essence of blockchain technology and the possibility of its application in the banking sector. The current state of development and application of blockchain technologies in various industries is analyzed. The pros and cons of using blockchain technologies for the banking sector are identified. Emphasis is placed on the role of blockchain technologies in the further development of the banking sector. The most promising directions of development of this technology are considered. Particular attention is paid to examples of the use of blockchain technology by global banking institutions.

How to make Russia a prosperous industrial country (about the role of the oil production and refining complex)

2020 ◽  
pp. 22-28
Author(s):  
Yu. Kanataev
Keyword(s):  
Precious Metals ◽  
Oil Production ◽  
Industrial Country ◽  
Industrial Scale ◽  
Deep Processing ◽  
Domestic Technology ◽  
Petrochemical Complex ◽  
Russian Economy ◽  
Further Development

The author, head of the Association of science-intensive enterprises having great experience in exploration of oil, precious metals, etc. in Russia and abroad (Austria, China, Israel, Ethiopia), first implemented on an industrial scale deep processing of oil using domestic technology, discusses the problems of further development of the Russian economy through the prism of their solutions to the main industries — oil and petrochemical complex.

Cartographic production in Russia: main stages and trends

2020 ◽  
Vol 963 (9) ◽  
pp. 30-43
Author(s):  
M.Yu. Orlov
Keyword(s):  
Chronological Order ◽  
Xviii Century ◽  
New Methods ◽  
Current State ◽  
Factors Influencing ◽  
The Future ◽  
History Of ◽  
State Enterprises ◽  
Further Development

Studying the current state of cartography and ways of further developing the industry, the role of the map in the future of the society, new methods of promoting cartographic products is impossible without a deep scientific analyzing all the paths, events and factors influencing its formation and development throughout all the historic steps of cartographic production in Russia. In the article, the history of cartographic production in Russia is considered together with the development of private, state and military cartography, since, despite some differences, they have a common technical, technological and production basis. The author describes the stages of originating, formation and growth of industrial cartographic production from the beginning of the XVIII century until now. The connection between the change of political formations and technological structures with the mentioned stages of maps and atlases production is considered. Each stage is studied in detail, a step-by-step analysis was carried out, and the characteristics of each stage are described. All the events and facts are given in chronological order, highlighting especially significant moments influencing the evolution of cartographic production. The data on the volumes of printing and sales of atlases and maps by commercial and state enterprises are presented. The main trends and lines of further development of cartographic production in Russia are studied.

scholarly journals Hospital chaplains as ethical consultants in making difficult medical decisions

2021 ◽  
pp. medethics-2020-107096
Author(s):  
Waldemar Głusiec
Keyword(s):  
Roman Catholic ◽  
Medical Decision ◽  
Medical Decisions ◽  
Hospital Chaplains ◽  
Specialist Knowledge ◽  
Hospital Ethics ◽  
Bioethical Education ◽  
Further Development

Background and aimsFew Polish hospitals have Hospital Ethics Committee (HECs) and the services are not always adequate. In this situation, the role of HECs, in providing, among others, ethical advice on the discontinuation of persistent therapies, may be taken over by other entities. The aim of our research was to investigate, how often and on what issues hospital chaplains are asked for ethical advice in reaching difficult medical decisions.MethodsA survey of 100 Roman Catholic chaplains was conducted, that is, at least 10% of all chaplains currently working in Polish hospitals.ResultsOf the participants, 29% confirmed receiving requests for advice in making a morally difficult medical decision. Receiving this type of request was not conditional on the place of their service, duration of their pastoral mission or HEC membership. The largest group of chaplains (21%) encounter questions concerning the ethical dilemmas associated with discontinuing persistent therapy. Patients and their families most often raise issues related to the methods of birth control, and the medical staff raise the issue of termination of pregnancy—as reported by 9% and 15% of chaplains, respectively. Most of the chaplains asked for help (79%) experience a deficit of specialist knowledge in the area of medicine or ethics.ConclusionsIn order to improve the quality of ethical consultations in Polish hospitals, in addition to further development of HECs, it is postulated to develop a system for bioethical education of chaplains.

scholarly journals Effect of Calcium Nitrate on the Properties of Portland–Limestone Cement-Based Concrete Cured at Low Temperature

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1611
Author(s):  
Gintautas Skripkiūnas ◽  
Asta Kičaitė ◽  
Harald Justnes ◽  
Ina Pundienė
Keyword(s):  
Compressive Strength ◽  
Cement Paste ◽  
Setting Time ◽  
Calcium Nitrate ◽  
Curing Temperature ◽  
Hardened Concrete ◽  
Cement Pastes ◽  
Initial Setting Time ◽  
Initial Setting ◽  
Early Strength

The effect of calcium nitrate (CN) dosages from 0 to 3% (of cement mass) on the properties of fresh cement paste rheology and hardening processes and on the strength of hardened concrete with two types of limestone-blended composite cements (CEM II A-LL 42.5 R and 42.5 N) at different initial (two-day) curing temperatures (−10 °C to +20 °C) is presented. The rheology results showed that a CN dosage up to 1.5% works as a plasticizing admixture, while higher amounts demonstrate the effect of increasing viscosity. At higher CN content, the viscosity growth in normal early strength (N type) cement pastes is much slower than in high early strength (R type) cement pastes. For both cement-type pastes, shortening the initial and final setting times is more effective when using 3% at +5 °C and 0 °C. At these temperatures, the use of 3% CN reduces the initial setting time for high early strength paste by 7.4 and 5.4 times and for normal early strength cement paste by 3.5 and 3.4 times when compared to a CN-free cement paste. The most efficient use of CN is achieved at −5 °C for compressive strength enlargement; a 1% CN dosage ensures the compressive strength of samples at a −5 °C initial curing temperature, with high early strength cement exceeding 3.5 MPa but being less than the required 3.5 MPa in samples with normal early strength cement.

scholarly journals Effect of C-S-H Nucleating Agent on Cement Hydration

2021 ◽  
Vol 11 (14) ◽  
pp. 6638
Author(s):  
Wenhao Zhao ◽  
Xuping Ji ◽  
Yaqing Jiang ◽  
Tinghong Pan
Keyword(s):  
Fractal Dimension ◽  
Cement Hydration ◽  
Nucleating Agent ◽  
Crystal Nucleation ◽  
Enhancement Effect ◽  
Hydration Products ◽  
Hydration Degree ◽  
Hydration Kinetics ◽  
Cement Mortars ◽  
Early Strength

This work aims to study the effect of a nucleating agent on cement hydration. Firstly, the C-S-H crystal nucleation early strength agent (CNA) is prepared. Then, the effects of CNA on cement hydration mechanism, early strength enhancement effect, C-S-H content, 28-days hydration degree and 28-days fractal dimension of hydration products are studied by hydration kinetics calculation, resistivity test, BET specific surface area test and quantitative analysis of backscattered electron (BSE) images, respectively. The results show that CNA significantly improves the hydration degree of cement mixture, which is better than triethanolamine (TEA). CNA shortens the beginning time of the induction period by 49.3 min and the end time of the cement hydration acceleration period by 105.1 min than the blank sample. CNA increases the fractal dimension of hydration products, while TEA decreases the fractal dimension. CNA significantly improves the early strength of cement mortars; the 1-day and 3-days strength of cement mortars with CNA are more than the 3-days and 7-days strength of the blank sample. These results will provide a reference for the practical application of the C-S-H nucleating agent.

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