scholarly journals Current challenges in thermodynamic aspects of rubber foam

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Supitta Suethao ◽  
Worachai Ponloa ◽  
Saree Phongphanphanee ◽  
Jirasak Wong-Ekkabut ◽  
Wirasak Smitthipong
Keyword(s):  
Thermodynamic Parameters ◽  
Activation Enthalpy ◽  
Dynamic Properties ◽  
Computational Modelling ◽  
Scientific Concept ◽  
New Approach ◽  
Chemical Agents ◽  
Thermodynamical Parameters ◽  
Matrix Concentration ◽  
Structure Properties

AbstractNatural rubber (NR) foam can be prepared by the Dunlop method using concentrated natural latex with chemical agents. Most previous studies have focused on the thermodynamic parameters of solid rubber in extension. The main objective of this study is to investigate the effect of the NR matrix concentration on the static and dynamic properties of NR foams, especially the new approach of considering the thermodynamic aspects of NR foam in compression. We found that the density and compression strength of NR foams increased with increasing NR matrix concentration. The mechanical properties of NR foam were in agreement with computational modelling. Moreover, thermodynamic aspects showed that the ratio of internal energy force to the compression force, Fu/F, and the entropy, S, increased with increasing matrix concentration. The activation enthalpy, ∆Ha, also increased with increasing matrix concentration in the NR foam, indicating the greater relaxation time of the backbone of the rubber molecules. New scientific concepts of thermodynamic parameters of the crosslinked NR foam in compression mode are proposed and discussed. Our results will improve both the knowledge and the development of rubber foams based on the structure–properties relationship, especially the new scientific concept of the thermodynamical parameters under compression.

The main reasons for substance formation and natural process manifestation

2021 ◽  
pp. 76-96
Author(s):  
Alexander Likhachev
Keyword(s):  
Thermodynamic Parameters ◽  
World History ◽  
Natural Process ◽  
Natural Materials ◽  
Main Factors ◽  
Composition Structure ◽  
The Impact ◽  
Insight Into ◽  
Structure Properties

Natural materials and processes represent the global substance reflecting and determining its formation and existence as a whole and in all its components. Revealing the reasons for their formation and manifestation is crucial. The paper highlights the two main factors: «influences» and «gradients». Influences are interpreted as the impact of some substances and events on other similar parameters, and gradients are vector changes and differences in systems composition, structure, properties, states, energy and thermodynamic parameters. To provide an insight into the role and significance of the above factors and reasons, an attempt was made to consider their potential manifestation throughout the general world history within the existing knowledge about it.

Managing biohazards and environmental safety

2016 ◽  
Author(s):  
Ferenc Kovari ◽  
Gilbert Park
Keyword(s):  
Psychological Factors ◽  
Critical Care Unit ◽  
Environmental Safety ◽  
New Approach ◽  
Safe Environment ◽  
Protective Gear ◽  
Chemical Agents ◽  
Chemical Hazard ◽  
As Stress ◽  
Regular Training

This chapter highlights the most common sources of biohazards in a critical care unit and points out the importance of a safe environment. Detailed information is provided on various biological and chemical agents, including risks posed by radiation. As part of the topic of health care ergonomics, various issues are discussed. Washing hands is the key to reducing biological hazards. Wearing appropriate protective gear minimizes the risk of chemical hazard. Complying with safety rules and attending regular training help avoiding risks resulting from handling dangerous materials, electronic equipment. As a new approach we included the potential risk of psychological factors such as stress and noise.

scholarly journals A New Approach to Detection of Changes in Multidimensional Patterns

2021 ◽  
Vol 11 (3) ◽  
pp. 217-227
Author(s):  
Tomasz Gałkowski ◽  
Adam Krzyżak ◽  
Zofia Patora-Wysocka ◽  
Zbigniew Filutowicz ◽  
Lipo Wang
Keyword(s):  
Abrupt Change ◽  
Dynamic Properties ◽  
Multivariate Functions ◽  
Jump Detection ◽  
New Approach ◽  
3 Dimensional ◽  
Fault Protection ◽  
Functions Of Two Variables ◽  
Abrupt Changes ◽  
Engineering Problems

Abstract In the paper we develop an algorithm based on the Parzen kernel estimate for detection of sudden changes in 3-dimensional shapes which happen along the edge curves. Such problems commonly arise in various areas of computer vision, e.g., in edge detection, bioinformatics and processing of satellite imagery. In many engineering problems abrupt change detection may help in fault protection e.g. the jump detection in functions describing the static and dynamic properties of the objects in mechanical systems. We developed an algorithm for detecting abrupt changes which is nonparametric in nature and utilizes Parzen regression estimates of multivariate functions and their derivatives. In tests we apply this method, particularly but not exclusively, to the functions of two variables.

scholarly journals Understanding memories of the Holocaust—A new approach to neural networks in the digital humanities

2019 ◽  
Vol 35 (1) ◽  
pp. 17-33
Author(s):  
Tobias Blanke ◽  
Michael Bryant ◽  
Mark Hedges
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Sentiment Analysis ◽  
Digital Humanities ◽  
Research Question ◽  
Real Life ◽  
Computational Modelling ◽  
The United States ◽  
New Approach ◽  
Distant Supervision

Abstract This article addresses an important challenge in artificial intelligence research in the humanities, which has impeded progress with supervised methods. It introduces a novel method to creating test collections from smaller subsets. This method is based on what we will introduce as distant supervision’ and will allow us to improve computational modelling in the digital humanities by including new methods of supervised learning. Using recurrent neural networks, we generated a training corpus and were able to train a highly accurate model that qualitatively and quantitatively improved a baseline model. To demonstrate our new approach experimentally, we employ a real-life research question based on existing humanities collections. We use neural network based sentiment analysis to decode Holocaust memories and present a methodology to combine supervised and unsupervised sentiment analysis to analyse the oral history interviews of the United States Holocaust Memorial Museum. Finally, we employed three advanced methods of computational semantics. These helped us decipher the decisions by the neural network and understand, for instance, the complex sentiments around family memories in the testimonies.

scholarly journals Structural Features, Modification, and Functionalities of Beta-Glucan

Fibers ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 1 ◽  
Author(s):  
Ramandeep Kaur ◽  
Minaxi Sharma ◽  
Dawei Ji ◽  
Min Xu ◽  
Dominic Agyei
Keyword(s):  
Molecular Weight ◽  
Functional Properties ◽  
Food Industry ◽  
Food Product ◽  
Structural Features ◽  
Enzyme Hydrolysis ◽  
Beta Glucan ◽  
Chemical Agents ◽  
Method Of Extraction ◽  
Structure Properties

Β-glucan is a strongly hydrophilic non-starchy polysaccharide, which, when incorporated in food, is renowned for its ability to alter functional characteristics such as viscosity, rheology, texture, and sensory properties of the food product. The functional properties of β-glucans are directly linked to their origin/source, molecular weight, and structural features. The molecular weight and structural/conformational features are in turn influenced by method of extraction and modification of the β-glucan. For example, whereas physical modification techniques influence only the spatial structures, modification by chemical agents, enzyme hydrolysis, mechanical treatment, and irradiation affect both spatial conformation and primary structures of β-glucan. Consequently, β-glucan can be modified (via one or more of the aforementioned techniques) into forms that have desired morphological, rheological, and (bio)functional properties. This review describes how various modification techniques affect the structure, properties, and applications of β-glucans in the food industry.

A new approach for proteases production by Aspergillus niger based on the kinetic and thermodynamic parameters of the enzymes obtained

2015 ◽  
Vol 4 (2) ◽  
pp. 199-207 ◽  
Author(s):  
Ruann Janser Soares de Castro ◽  
André Ohara ◽  
Tânia Goia Nishide ◽  
Juliana Reolon Mangabeira Albernaz ◽  
Marília Herculano Soares ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Thermodynamic Parameters ◽  
New Approach ◽  
Kinetic And Thermodynamic Parameters

The evolutionary bootstrap: a new approach to the study of taxonomic diversity

Paleobiology ◽  
1986 ◽  
Vol 12 (3) ◽  
pp. 251-268 ◽  
Author(s):  
Norman L. Gilinsky ◽  
Richard K. Bambach
Keyword(s):  
Null Hypothesis ◽  
Dynamic Properties ◽  
Taxonomic Diversity ◽  
New Approach ◽  
The Real ◽  
Statistical Verification ◽  
Large Numbers ◽  
Random Expectation ◽  
History Of ◽  
End Members

The evolutionary bootstrap is a new approach to the analysis of patterns of taxonomic diversity. In general, the evolutionary bootstrap works by surveying the diversity history of a taxon, learning its dynamic properties, and then generating randomly large numbers of artificial diversity histories based upon what was learned. The distribution of artificial—or bootstrapped—diversity histories approximates the distribution of diversity histories that were possible for taxa with the dynamic properties of the real taxon, and serves as a paleontological null hypothesis for studying statistically the diversity history of the real taxon.Two null hypotheses were established, the additive and the multiplicative. The additive null hypothesis assumes that the amount of diversity change that occurs in a higher taxon during an interval of time is independent of the number of member subtaxa present at the beginning of the interval. The multiplicative null hypothesis, in contrast, assumes that the amount of diversity change that occurs is dependent upon the number of member subtaxa present at the start. Thus the two null hypotheses represent end members of a diversity-independent/diversity-dependent continuum of possibilities.Detailed analyses using the evolutionary bootstrap, in conjunction with the clade statistics of Gould et al. (1977), show that several of the 17 higher taxa studied have diversity histories that are statistically significantly different from the random expectation under one or both null hypotheses. Analyses of multiple taxa in aggregate also reveal several properties of diversity histories that are statistically significantly different from random. Real taxa tend to have higher uniformities and lower maximum diversities than expected under the multiplicative null hypothesis. They have lower uniformities, higher maximum diversities, and longer durations than expected under the additive null hypothesis. And, they have lower centers of gravity than expected under either null hypothesis. Overall, the results provide a possible statistical verification of the process of taxonomic (traditionally, adaptive) radiation and suggest the need to consider deterministic explanations for observed diversity patterns.

Neural competition and statistical mechanics

1996 ◽  
Vol 263 (1370) ◽  
pp. 601-606 ◽  
Keyword(s):  
Statistical Mechanics ◽  
Neural Plasticity ◽  
Computational Models ◽  
Computational Modelling ◽  
New Approach ◽  
Target Innervation ◽  
Wide Range ◽  
Pharmacological Manipulations ◽  
Activity Dependent ◽  
Neural Competition

Computational models of activity-dependent competitive neural plasticity typically impose competition in networks in which plasticity is accommodated by permitting changes in the efficacies of synapses in an anatomically fixed network. This is despite the fact that much evidence suggests that neurons compete for neurotrophins, during both target innervation and activity-dependent synaptic re-arrangement, which influence the sprouting and retraction of axonal processes. We therefore present a new approach to the computational modelling of competitive neural plasticity which permits neurons to compete explicitly for neurotrophins. This competition is associated with the sprouting and retraction of axonal processes. Because there is much uncertainty regarding the basic mechanisms, we adopt the powerful machinery of statistical mechanics to avoid the need to address these issues. We show that such an approach can readily account for a wide range of plasticity phenomena in a range of systems, including the results of various pharmacological manipulations.

scholarly journals Advocating a New Approach to Governing Water, Energy, and Food Security: Testing the Effects of Message Inoculation and Conclusion Explicitness in the Case of the WEF Nexus

2018 ◽  
Vol 1 (1) ◽  
pp. 111-134 ◽  
Author(s):  
Qingjiang Yao ◽  
Praphul Joshi ◽  
Chiung-Fang Chang ◽  
Chelsea McDonalds ◽  
Jason Tran ◽  
...  
Keyword(s):  
Food Security ◽  
Scientific Concept ◽  
Security Testing ◽  
Total N ◽  
New Approach ◽  
The Public ◽  
Negative Side ◽  
Message Sidedness

Message sidedness, including its later format inoculation, and conclusion explicitness have been identified by researchers as two prominent message factors that may influence advocating effects. Two-sided messages, which contain both supporting and opposing information about the issue, particularly those containing inoculation components that refute the negative side, are found to be more effective than one-sided messages. Messages with explicit conclusions are also found to be more persuasive than those that let the audience draw the conclusions themselves. This study tested the persuasion effectiveness of message inoculation and conclusion explicitness on a new scientific concept, the water–energy–food (WEF) nexus, of which the public has little knowledge. This study used five randomly assigned groups (total N = 524) and found that messages with explicit conclusions are more persuasive than those with implicit conclusions; however, it found no difference between the effectiveness of one-sided messages and of refutational two-sided messages. The study suggests that a clear conclusion is necessary to communicate the WEF nexus for a better approach to managing the megacrisis of water, energy, and food security.

scholarly journals Mathematical Modeling of a Supramolecular Assembly for Pyrophosphate Sensing

2021 ◽  
Vol 9 ◽  
Author(s):  
Fereshteh Emami ◽  
Hamid Abdollahi ◽  
Tsyuoshi Minami ◽  
Ben Peco ◽  
Sean Reliford
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Models ◽  
Thermodynamic Parameters ◽  
Dynamic Properties ◽  
Phenylboronic Acid ◽  
Binding Constants ◽  
Supramolecular Assembly ◽  
Alizarin Red ◽  
Chemical Systems ◽  
New Sensors

The power of sensing molecules is often characterized in part by determining their thermodynamic/dynamic properties, in particular the binding constant of a guest to a host. In many studies, traditional nonlinear regression analysis has been used to determine the binding constants, which cannot be applied to complex systems and limits the reliability of such calculations. Supramolecular sensor systems include many interactions that make such chemical systems complicated. The challenges in creating sensing molecules can be significantly decreased through the availability of detailed mathematical models of such systems. Here, we propose uncovering accurate thermodynamic parameters of chemical reactions using better-defined mathematical modeling-fitting analysis is the key to understanding molecular assemblies and developing new bio/sensing agents. The supramolecular example we chose for this investigation is a self-assembled sensor consists of a synthesized receptor, DPA (DPA = dipicolylamine)-appended phenylboronic acid (1) in combination with Zn2+(1.Zn) that forms various assemblies with a fluorophore like alizarin red S (ARS). The self-assemblies can detect multi-phosphates like pyrophosphate (PPi) in aqueous solutions. We developed a mathematical model for the simultaneous quantitative analysis of twenty-seven intertwined interactions and reactions between the sensor (1.Zn-ARS) and the target (PPi) for the first time, relying on the Newton-Raphson algorithm. Through analyzing simulated potentiometric titration data, we describe the concurrent determination of thermodynamic parameters of the different guest-host bindings. Various values of temperatures, initial concentrations, and starting pHs were considered to predict the required measurement conditions for thermodynamic studies. Accordingly, we determined the species concentrations of different host-guest bindings in a generalized way. This way, the binding capabilities of a set of species can be quantitatively examined to systematically measure the power of the sensing system. This study shows analyzing supramolecular self-assemblies with solid mathematical models has a high potential for a better understanding of molecular interactions within complex chemical networks and developing new sensors with better sensing effects for bio-purposes.

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