Studying the Relationship between the Strength and Stress-Related Characteristics of Concrete as a Conglomerate and the Properties of its Components

2021 ◽  
Vol 1022 ◽  
pp. 71-79
Author(s):  
Evgeniy M. Shcherban ◽  
Sergey A. Stelmakh ◽  
Aleksandr Sysoev ◽  
Andrei Chernil'nik
Keyword(s):  
Axial Compression ◽  
Experimental Tests ◽  
Cement Stone ◽  
Axial Tensile ◽  
Number Of Factors ◽  
Shrinkage And Creep ◽  
The Matrix ◽  
Load Action ◽  
The Relationship

The concrete conglomerate properties change over time and depend on a number of factors. When considering deformation under the effect of mechanical loads or changes in temperature and humidity, the mechanism of this process is based on three main provisions. Firstly, concrete is a composite material, the matrix of which is cement stone. Secondly, the elastic modulus and strength of the cement stone may be less or more than that of aggregate. Thirdly, the concrete destruction under axial compression occurs at the cement stone stresses exceeding its ultimate extensibility in the direction normal to the external load action. Considering the specifics of deformation under load in different periods and the role of stress-related characteristics in this process, it is advisable to outline ways to regulate them and thereby the main concrete properties in the desired direction. The importance and feasibility of this approach are determined by the need to develop techniques allowing control of properties such as elasticity, shrinkage, and creep. A series of experimental tests and a comparative analysis of the results have been performed. The effect of some aggregate rocks on certain strength and stress-related properties of the concrete conglomerate has been investigated. Limestone and sandstone have been taken as the rocks studied. The properties studied include impact, axial compression, and axial tensile strengths. According to the analysis, concrete prepared on crushed limestone has shown the best results concerning all the properties studied.

Simulation and Experimental Study of the Coupling Drive Magnetic Field for Embedded Giant Magnetostrictive Actuators

2012 ◽  
Vol 510 ◽  
pp. 322-327
Author(s):  
Bin Wang ◽  
Yi Jie Wu ◽  
Lei Zhang
Keyword(s):  
Magnetic Field ◽  
Matrix Material ◽  
Experimental Tests ◽  
High Frequencies ◽  
Output Displacement ◽  
Close Relationship ◽  
The Matrix ◽  
Magnetostrictive Actuators ◽  
Magnetostrictive Actuator ◽  
The Relationship

Embedded giant magnetostrictive actuator (EGMA) is one of the most important applications of magnetostrictive material. Giant magnetostrictive actuators can deliver big-output displacement and can be driven at high frequencies. These characteristics make them suitable for a variety of positioning. However, because of the limitation of structure, the drive coil and EGMA cannot be any size as needed, so how to maximize the displacement in the limitative situation by optimization becomes the key of design. Several methods are available in the literature, but the coupling drive magnetic field of EGMA and its matrix material is often ignored. In fact, there was a close relationship between the matrix material and the distribution of drive magnetic field. To analyze the relationship, this paper establishes the magnetic circuit model for EGMA. The simulation of the coupling drive magnetic field is also presented. Finally the assumption is validated through experimental tests carried out with two different matrix materials.

The family and compliance in schizophrenia: the influence of clinical variables, relatives' knowledge and expressed emotion

2002 ◽  
Vol 33 (1) ◽  
pp. 91-96 ◽  
Author(s):  
W. SELLWOOD ◽  
N. TARRIER ◽  
J. QUINN ◽  
C. BARROWCLOUGH
Keyword(s):  
Social Functioning ◽  
Expressed Emotion ◽  
Family Intervention ◽  
Psychotic Symptoms ◽  
Number Of Factors ◽  
The Family ◽  
Two Factors ◽  
The Subject ◽  
The Relationship

Background. A variety of factors are related to compliance with medication in schizophrenia, but little attention has been paid to the role of families. Carers' knowledge or expressed emotion (EE) may be related to compliance. The aim of the present study was to evaluate the relevance of these two factors, as well as their relationships with other variables for the prediction of compliance.Method. A sample of patient–carer pairs (N=79) involved in a family intervention for schizophrenia trial was recruited. Compliance, symptoms, social functioning and attitudes to their carers were assessed in patients. Carers' EE, knowledge and psychopathology were also evaluated.Results. A number of factors were related to compliance, including carers' EE and patients' psychotic symptoms, which contributed independently to not taking medication. Carers' knowledge about schizophrenia and other groups of symptoms was not related to compliance.Conclusions. EE may be an important factor to account for in the understanding of patients' compliance and the direction of the relationship between EE and compliance should be the subject of further study.

Filament Fragmentation Phenomena

1989 ◽  
Vol 170 ◽  
Author(s):  
Juan C. Figueroa ◽  
Linda S. Schadler ◽  
Campbell Laird
Keyword(s):  
Strain Energy ◽  
Stress Transfer ◽  
Fiber Surface ◽  
Yield Information ◽  
The Matrix ◽  
Two Parameters ◽  
The Relationship

AbstractThe effect of fiber surface treatments on the relationship between the tensile strength of a filament and the shear strength of its interphase is one of the central issues facing composite materials technologists today. We demonstrate here that analysis of fragmentation phenomena in monofilament composites can simultaneously yield information about these two parameters. Characterization of shear stress transfer zones in non-critical fragments has led us to the determination of interphase strength.A phenomenological treatment that highlights the role of the matrix in the fragmentation process is presented here. This analysis considers issues such as the strain energy exchange between a failing fiber and the matrix, as well as interphase relaxation due to the viscoelastic nature of the matrix. Our observations of the fragmentation phenomena in AU4/polycarbonate monofilament composites indicate that the fiber/matrix interaction in this system is governed by micromechanical locking.

scholarly journals Key Role of the Dispersion of Carbon Nanotubes (CNTs) within Epoxy Networks on their Ability to Release

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2530
Author(s):  
Maxime Pras ◽  
Jean-François Gérard ◽  
Luana Golanski ◽  
Guilhem Quintard ◽  
Jannick Duchet-Rumeau
Keyword(s):  
Polymer Matrix ◽  
Interfacial Strength ◽  
Advanced Materials ◽  
Mechanical Reinforcement ◽  
Rheological Analysis ◽  
Polymerization Kinetic ◽  
The Matrix ◽  
Dispersion State ◽  
The Relationship

Carbon nanotube (CNT)-reinforced nanocomposites represent a unique opportunity in terms of designing advanced materials with mechanical reinforcement and improvements in the electrical and thermal conductivities. However, the toxic effects of these composites on human health have been studied, and very soon, some regulations on CNTs and on composites based on CNTs will be enacted. That is why the release of CNTs during the nanocomposite lifecycle must be controlled. As the releasing depends on the interfacial strength that is stronger between CNTs and polymers compared to CNTs in a CNT agglomerate, two dispersion states—one poorly dispersed versus another well dispersed—are generated and finely described. So, the main aim of this study is to check if the CNT dispersion state has an influence on the CNT releasing potential in the nanocomposite. To well tailor and characterize the CNT dispersion state in the polymer matrix, electronic microscopies (SEM and TEM) and also rheological analysis are carried out to identify whether CNTs are isolated, in bundles, or in agglomerates. When the dispersion state is known and controlled, its influence on the polymerization kinetic and on mechanical properties is discussed. It appears clearly that in the case of a good dispersion state, strong interfaces are generated, linking the isolated nanotubes with the polymer, whereas the CNT cohesion in an agglomerate seems much more weak, and it does not provide any improvement to the polymer matrix. Raman spectroscopy is relevant to analyze the interfacial properties and allows the relationship with the releasing ability of nanocomposites; i.e., CNTs poorly dispersed in the matrix are more readily released when compared to well-dispersed nanocomposites. The tribological tests confirm from released particles granulometry and observations that a CNT dispersion state sufficiently achieved in the nanocomposite avoids single CNT releasing under those solicitations.

scholarly journals ESG factors as tool for forming business reputation

2021 ◽  
Vol 2021 (4) ◽  
pp. 15-21
Author(s):  
Irina Yur'evna Belayeva ◽  
Nadezhda Pavlovna Kozlova ◽  
Olga Viktorovna Danilova
Keyword(s):  
Profit Maximization ◽  
Investment Strategies ◽  
The Sustainable Development ◽  
Number Of Factors ◽  
Environmentally Responsible ◽  
Degree Of Satisfaction ◽  
Responsible Attitude ◽  
The Relationship

The article focuses on the ESG factors determining the activities of most companies in recent years. The relationship between ESG principles and the business reputation of a modern company has been indicated. Business reputation is found to be formed under the influence of a number of factors, among which a responsible attitude to the environment, social responsibility and the quality of corporate governance have come out in the first place in recent years. The analysis proved that the ESG principles are firmly entrenched abroad, the number of companies with an ESG rating is growing exponentially, and their profitability is increasing. It has been stated that the Russian business has not yet included ESG principles as mandatory parameters of active investment strategies. The emphasis is put on the relationship with stakeholders, since it is the stakeholders who evaluate the company's activities from the standpoint of the degree of satisfaction of their needs. The conducted analysis has proved that an assessment includes not only profit maximization and dividend growth, but also the results of social and environmentally responsible practices of companies. It has been inferred that there is a relationship between the sustainable development of the company, its business reputation, the creation of ethical values and taking into account the interests of stakeholders in the company's strategy. It is emphasized that ESGs become an instrument of active investment strategies and a tool that determines the business reputation of the company. The practice of responsible ESG investment has been illustrated, the role of institutional investors in the dissemination of this practice has been highlighted.

scholarly journals Dynamics of matrix-free Ca2+ in cardiac mitochondria: two components of Ca2+ uptake and role of phosphate buffering

2012 ◽  
Vol 139 (6) ◽  
pp. 465-478 ◽  
Author(s):  
An-Chi Wei ◽  
Ting Liu ◽  
Raimond L. Winslow ◽  
Brian O'Rourke
Keyword(s):  
Mitochondrial Permeability Transition ◽  
High Capacity ◽  
Permeability Transition Pore ◽  
Permeability Transition ◽  
Cardiac Mitochondria ◽  
The Matrix ◽  
The Relationship ◽  
Matrix Free ◽  
Trigger Cell Death

Mitochondrial Ca2+ uptake is thought to provide an important signal to increase energy production to meet demand but, in excess, can also trigger cell death. The mechanisms defining the relationship between total Ca2+ uptake, changes in mitochondrial matrix free Ca2+, and the activation of the mitochondrial permeability transition pore (PTP) are not well understood. We quantitatively measure changes in [Ca2+]out and [Ca2+]mito during Ca2+ uptake in isolated cardiac mitochondria and identify two components of Ca2+ influx. [Ca2+]mito recordings revealed that the first, MCUmode1, required at least 1 µM Ru360 to be completely inhibited, and responded to small Ca2+ additions in the range of 0.1 to 2 µM with rapid and large changes in [Ca2+]mito. The second component, MCUmode2, was blocked by 100 nM Ru360 and was responsible for the bulk of total Ca2+ uptake for large Ca2+ additions in the range of 2 to 10 µM; however, it had little effect on steady-state [Ca2+]mito. MCUmode1 mediates changes in [Ca2+]mito of 10s of μM, even in the presence of 100 nM Ru360, indicating that there is a finite degree of Ca2+ buffering in the matrix associated with this pathway. In contrast, the much higher Ca2+ loads evoked by MCUmode2 activate a secondary dynamic Ca2+ buffering system consistent with calcium-phosphate complex formation. Increasing Pi potentiated [Ca2+]mito increases via MCUmode1 but suppressed [Ca2+]mito changes via MCUmode2. The results suggest that the role of MCUmode1 might be to modulate oxidative phosphorylation in response to intracellular Ca2+ signaling, whereas MCUmode2 and the dynamic high-capacity Ca2+ buffering system constitute a Ca2+ sink function. Interestingly, the trigger for PTP activation is unlikely to be [Ca2+]mito itself but rather a downstream byproduct of total mitochondrial Ca2+ loading.

scholarly journals ACE Insertion/Deletion Polymorphism and Diabetic Nephropathy: Clinical Implications of Genetic Information

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Sung-Kyu Ha
Keyword(s):  
Diabetic Nephropathy ◽  
Sodium Intake ◽  
Developed Countries ◽  
Initial Study ◽  
Renal Diseases ◽  
Diabetic Patients ◽  
Number Of Factors ◽  
Antiproteinuric Effect ◽  
The Relationship

Approximately 20–40% of diabetic patients develop nephropathy which is the leading cause of ESRD in developed countries. The ACE I/D polymorphism is thought to be a marker for functional polymorphism which regulates circulating and tissue ACE activity. While the initial study found a protective effect of the II genotype on the development of nephropathy in IDDM patients, subsequent studies have addressed the role of ACE I/D polymorphism in the development and progression of diabetic nephropathy. RAAS blockers are the first line drugs for the treatment hypertension associated with diabetes and have been widely used in everyday clinical practice for the purpose of reducing proteinuria in patients with various renal diseases. However, the antiproteinuric effect of RAAS blockers is variable and the percentage of reducing proteinuria is in the range of 20–80%. The antiproteinuric effect of RAAS blockers may be related to a number of factors: the type or the dose of RAAS blockers, the duration of therapy, the level of sodium intake, and the type of patient’s ACE I/D genotype. Besides the nongenetic factors, drug responses, can be influenced by ACE gene polymorphism. In this review, we discuss the relationship between ACE I/D polymorphism and diabetic nephropathy and therapeutic response of RAAS blockers.

scholarly journals Relating in vitro neutralisation level and protection in the CVnCoV (CUREVAC) trial.

2021 ◽  
Author(s):  
Deborah Cromer ◽  
Arnold Reynaldi ◽  
Megan Steain ◽  
James A Triccas ◽  
Miles Philip Davenport ◽  
...  
Keyword(s):  
Antibody Response ◽  
Potential Role ◽  
Vaccine Candidate ◽  
High Efficacy ◽  
Number Of Factors ◽  
The Relationship

A recent study analysed the relationship between neutralising antibody response and protection from SARS-CoV-2 infection across eight vaccines platforms. The efficacy results from a phase 2b/3 trial of a ninth vaccine candidate, CVnCoV (CUREVAC), was announced on 16 June 2021. The low efficacy of this new mRNA vaccine, which showed only 47% protection from symptomatic SARS-CoV-2 infection, was surprising, given the high efficacy of two previous mRNA-based vaccines. A number of factors have been suggested to play a role in the low efficacy in the CVnCoV study, particularly around the dose and immunogenicity of the vaccine (which uses a slightly different mRNA construct) and the potential role of infection with SARS-CoV-2 variants (which were the dominant strains observed in the CVnCoV trial).

Deformation Twinning in Hadfield Steel

2013 ◽  
Vol 772 ◽  
pp. 62-67 ◽  
Author(s):  
A.A. Yeleussizova ◽  
М.K. Skakov ◽  
А.M. Zhilkashinova ◽  
O.V. Rofman
Keyword(s):  
Strain Hardening ◽  
Deformation Twinning ◽  
Hadfield Steel ◽  
Number Of Factors ◽  
The Matrix ◽  
Slip Planes ◽  
Schmid Factor ◽  
Final Effect ◽  
Strain Hardening Rate

The deformation twinning leads to a reduction of the coefficient of strain hardening, i.e. twinning plays an important role in deformation of steel. The contribution of twinning to the total deformation is significant (up to 1/3 of the overall deformation). The final effect of twinning on strain hardening rate depends on the number of factors introduced by the twinning itself in the process of sliding. Calculated Schmid factors for slip systems operating in the matrix and in the twin. The analysis of the twinning geometry in particular grains showed that twinning is primarily developed for systems with the highest Schmid factor. However, twinning was also observed with a minimum and even zero Schmid factor. The obtained results indicate the importance of the orientation of slip planes in the newly formed micro-twins and Schmid factors for twinning. The important role of crystallographic texture in the physics of strain hardening was also shown.

scholarly journals The Role of Investors and Financiers’ Support in Globalization of Pakistani Companies

2018 ◽  
pp. 39-55
Author(s):  
Jawaid Ahmed Qureshi ◽  
Muhammad Asif Qureshi ◽  
Amanat Ali Jalbani
Keyword(s):  
Bank Lending ◽  
Business Network ◽  
Second Stage ◽  
Corporate Globalization ◽  
The Matrix ◽  
Global Skills ◽  
Global Investors ◽  
Domestic Economies ◽  
The Relationship

In the regime of globalization, many companies around the world attempt to globalize their business network beyond domestic boundaries. The stimulus behind that is to nourish, avail opportunities, and earn profits by leveraging the global skills and resources. Such an extension of business can not only benefit them but also to the domestic economies, and overseas economies too in many respects. This study intensively examines the way investors and financers’ assist Pakistani companies to expand their business worldwide. When companies flourish their business ventures and even go global, investors feel confident in investing with them. Similarly, financers trust them and finance them at soft/discounted terms. This is a novel study in the matrix of Pakistan. One earlier research on this issue in some other country ascertained only about the role of bank lending in corporate globalization, while this probe also enlarges its scope by probing about the relationship among investors and globally expanding companies.           The research design of this study consists of sequential hybrid research approaches. At the first stage, a qualitative study was conducted to have basic acquaintance about the core theme of the investigation, corporate globalization and the role of investors and banks cum lending agencies to support Pakistani companies. At the second stage, quantitative study was conducted to test the hypotheses. The samples belong to the population of top-five export-oriented sectors in Pakistan since many of their companies have globalized their operations. The findings reveal evidence of trust and support by investors, banks, and lending entities to these companies.

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