scholarly journals BITUMENS AND POLYMER BITUMENS - NANODISPERSE SYSTEMS

2021 ◽  
Vol 445 (1) ◽  
pp. 172-176
Author(s):  
M. Zh. Zhurinov ◽  
B. B. Teltayev
Keyword(s):  
Point Of View ◽  
Chemical Compositions ◽  
Direct Impact ◽  
Colloid Chemistry ◽  
The Road ◽  
Reactive Polymers ◽  
Group Chemical ◽  
Group Compositions

This work shows the data regarding the elemental and chemical group compositions of the road bitumens. The short characteristic has been shown for the components of the bitumens - the asphaltenes, the resins and the oils. The properties have been described for the bitumens on which they have the direct impact. The description is given for the micellar model of the bitumens from the point of view of the colloid chemistry. The analysis has been performed for the results of the study by other authors for the asphaltenes of a bitumen and an oil. The group chemical compositions are given for the bitumen of the grades BND 50/70, BND 70/100 and BND 100/130 produced by the plants of Kazakhstan. It has been shown that the content of the asphaltenes in them is from 15.8% to 24.3%; in most cases, the content of the asphaltenes is within the range of 20-25%, i.e. the asphaltenes nanoclusters are almost a fourth of the bitumen by weight. The brief description is given for the best known polymers used for the modification of the road bitumen: 1) the reactive polymers Elvaloy 4170 and Elvaloy AM; 2) the polymers of the group SBS - Kraton D 1192A, Calprene 501, SBS L 30-01 A, KUMHO KTR and Butonal NS 198. It is proposed to consider the bitumen and the polymer bitumen as the peculiar nanodisperse systems. The structures are described for the polymer bitumen nanodisperse systems occurring during the modification of the road bitumen with the polymers of the above two groups.

Electron microprobe study of turquoise-group solid solutions in the Neyshabour and Meydook mines, northeast and southern Iran

2020 ◽  
Vol 58 (1) ◽  
pp. 71-83
Author(s):  
Elahe Mansouri Gandomani ◽  
Nematollah Rashidnejad-Omran ◽  
Amir Emamjomeh ◽  
Pietro Vignola ◽  
Tahereh Hashemzadeh
Keyword(s):  
Solid Solution ◽  
Solid Solutions ◽  
Electron Microprobe ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Major Elements ◽  
Point Of View ◽  
Chemical Compositions ◽  
Light Blue ◽  
Quaternary Solid Solution

ABSTRACT Turquoise, CuAl6(PO4)4(OH)8·4H2O, belongs to the turquoise group, which consists of turquoise, chalcosiderite, aheylite, faustite, planerite, and UM1981-32-PO:FeH. In order to study turquoise-group solid solutions in samples from the Neyshabour and Meydook mines, 17 samples were selected and investigated using electron probe microanalysis. In addition, their major elements were compared in order to evaluate the feasibility of distinguishing the provenance of Persian turquoises. The electron microprobe data show that the studied samples are not constituted of pure turquoise (or any other pure endmember) and belong, from the chemical point of view, to turquoise-group solid solutions. In a turquoise–planerite–chalcosiderite–unknown mineral quaternary solid solution diagram, the chemical compositions of the analyzed samples lie along the turquoise–planerite line with minor involvement of chalcosiderite and the unknown mineral. Among light blue samples with varying hues and saturations from both studied areas, planerite is more abundant among samples from Meydook compared with samples from Neyshabour. Nevertheless, not all the light blue samples are planerite. This study demonstrates that distinguishing the deposit of origin for isochromatic blue and green turquoises, based on electron probe microanalysis method and constitutive major elements, is not possible.

scholarly journals The Road to Modern Logic—An Interpretation

2001 ◽  
Vol 7 (4) ◽  
pp. 441-484 ◽  
Author(s):  
José Ferreirós
Keyword(s):  
Order Logic ◽  
Point Of View ◽  
First Order Logic ◽  
Theoretical Point ◽  
Primary Role ◽  
Philosophical Discussion ◽  
Modern Logic ◽  
Core System ◽  
First Order ◽  
The Road

AbstractThis paper aims to outline an analysis and interpretation of the process that led to First-Order Logic and its consolidation as a core system of modern logic. We begin with an historical overview of landmarks along the road to modern logic, and proceed to a philosophical discussion casting doubt on the possibility of a purely rational justification of the actual delimitation of First-Order Logic. On this basis, we advance the thesis that a certain historical tradition was essential to the emergence of modern logic; this traditional context is analyzed as consisting in some guiding principles and, particularly, a set of exemplars (i.e., paradigmatic instances). Then, we proceed to interpret the historical course of development reviewed in section 1, which can broadly be described as a two-phased movement of expansion and then restriction of the scope of logical theory. We shall try to pinpoint ambivalencies in the process, and the main motives for subsequent changes. Among the latter, one may emphasize the spirit of modern axiomatics, the situation of foundational insecurity in the 1920s, the resulting desire to find systems well-behaved from a proof-theoretical point of view, and the metatheoretical results of the 1930s. Not surprisingly, the mathematical and, more specifically, the foundational context in which First-Order Logic matured will be seen to have played a primary role in its shaping.Mathematical logic is what logic, through twenty-five centuries and a few transformations, has become today. (Jean van Heijenoort)

THE ROAD AHEAD TO BETTER MEDICAL CARE FOR CHILDREN

PEDIATRICS ◽  
1950 ◽  
Vol 6 (3) ◽  
pp. 553-556
Keyword(s):  
Child Health ◽  
Medical Care ◽  
Medical Center ◽  
Point Of View ◽  
Medical Services ◽  
High Quality ◽  
The Road ◽  
Provide Child Care ◽  
Ultimate Objective ◽  
The Many

THE road to better child health has been discussed in relation to the doctor and his training, health services and their distribution. We have dealt with the unavoidable question of costs. Particular attention has been given to some of the advantages and dangers of decentralization of pediatric education and services. Each of the various subjects has been discussed from the point of view of its bearing on the ultimate objective of better health for all children and the steps necessary to attain this goal. Now, we may stand back from the many details of the picture, view the whole objectively and note its most outstanding features. First is the fact that the improvement of child health depends primarily upon better training for all doctors who provide child care, general practitioners as well as specialists. This is the foundation without which the rest of the structure cannot stand. The second dominant fact is the need for extending to outlying and isolated areas the high quality medical care of the medical centers, without at the same time diluting the service or training at the center. The road to better medical care, therefore, begins at the medical center and extends outward through a network of integrated community hospitals and health centers, finally reaching the remote and heretofore isolated areas. Inherent in all medical schools is a unique potential for rendering medical services as well as actually training physicians. The very nature of medical education—whereby doctors in training work under the tutelage of able specialists in the clinic, hospital ward, and out-patient department—provides medical services of high quality to people in the neighboring communities.

scholarly journals Design & Weight Optimization of a Wheel Rim for Sport Utility Vehicle.

2018 ◽  
Vol 172 ◽  
pp. 03006
Author(s):  
Harish Panjagala ◽  
Balakrishna M ◽  
Shasikant Kushnoore ◽  
E L N Rohit Madhukar
Keyword(s):  
Structural Analysis ◽  
Point Of View ◽  
Weight Optimization ◽  
Strength Assessment ◽  
Suitable Material ◽  
The Road ◽  
Wheel Rim ◽  
Standard Values ◽  
Design Weight ◽  
Structural Point

Automobile have various parts which are important for good running of the vehicle. The most important safety components from a structural point of view are the road wheels. They are required to be lighter and more fascinating to the buyer all the time. This implies that it's important to perform a lot of accurate strength assessment on wheel styles. The wheel rim plays a major role in vehicle dynamics. This paper deals with the design and model of different wheel rims based on weight optimization and also structural analysis has been carried out. It has been compared with standard values by varying two different materials. In addition, from the obtained outputs of simulations and the weight optimization, we suggested Aluminium alloys as most suitable material for SUV. Model is created by using SOLIDWORKS software 2015 and structural analysis &; weight optimization is done by using ANSYS WORKBENCH 16.0.

Relationship between Laboratory Abrasion Tests and Service Performance

1949 ◽  
Vol 22 (3) ◽  
pp. 838-862 ◽  
Author(s):  
T. R. Griffith ◽  
E. B. Storey ◽  
J. W. D. Barkley ◽  
F. M. McGilvray
Keyword(s):  
Abrasion Resistance ◽  
National Research Council ◽  
Point Of View ◽  
Viscous Material ◽  
The Road ◽  
Canadian National Research Council ◽  
Air Jet ◽  
Engineering Department ◽  
On The Road ◽  
Department Of National Defence

Abstract In development work on GR-S commercial recapping compounds originated in 1943 by the Directorate of Mechanical Engineering, Department of National Defence, Ottawa, Canada, in which an attempt was made to correlate road performance with physical properties as determined in the laboratory, it was found that no relationship whatever existed between the results of road tests carried out under the supervision of that directorate and standard laboratory abrasion resistance tests carried out in the Canadian National Research Council Rubber Laboratory at Ottawa. In the laboratory test the sandpaper in the abrasion machine became coated with a smear of tacky viscous material which the air jet was unable to remove. Under these conditions the rubber tends to slide over the sandpaper surface, with relatively little actual abrasion of the rubber. The effect remains even after a considerable overcure of the sample. It was felt that the removal of the tacky viscous material from vulcanized GR-S by extraction might give more reliable abrasion resistance results, inasmuch as, on the road, rubber is constantly coming in contact with a new surface and such viscous material is thus being continually removed as it migrates to the surface of the rubber. From this point of view, then, the tread surface while being abraded on the road may be looked upon as extracted rubber and may be considered as conforming closely to the extracted laboratory specimen.

A discussion on ship technology in the 1980s - Shipbuilding in the future

1972 ◽  
Vol 273 (1231) ◽  
pp. 13-21 ◽  
Keyword(s):  
Industrial Development ◽  
Manufacturing Industry ◽  
Group Technology ◽  
Modern Technology ◽  
Point Of View ◽  
Production Lines ◽  
The Road ◽  
Craft Industry ◽  
And Control ◽  
Capital Intensive

The growth in world trade and hence the demand for shipping is expected to continue into the 1980s despite the present temporary recession. Many countries in the Mediterranean and Pacific area and in South and Central America see shipbuilding as their way to start along the road to industrial development, and will be favoured by good climatic and labour conditions which can now be joined to imported modern technology. Conventional shipbuilding will therefore grow rapidly in these countries. Western countries will be able to preserve their shipbuilding industries by keeping in the forefront ol technical development and by a rigorous examination of designs from the production point of view, in order to reduce the labour content, and make the management and control simpler. This means changing from a largely labour intensive craft industry to a capital intensive, manufacturing industry. In order to sustain this type of industry long runs of similar ships, standard components, modulai constructions much of it in production lines, using group technology, will be the pattern in the 1980s. Much research and development is already devoted to these techniques and the industry is already at the early stages of changing over to this type of working.

scholarly journals The Effects of Divided Attention on Memory for Road Signs

2021 ◽  
Vol 26 (3) ◽  
pp. 283-295
Author(s):  
Nathaniel L. Foster ◽  
Gregory R. Bell
Keyword(s):  
Working Memory ◽  
Divided Attention ◽  
Incidental Learning ◽  
Correct Recall ◽  
Point Of View ◽  
Long Term Memory ◽  
The Road ◽  
Road Signs ◽  
Stop Sign ◽  
Naturalistic Environment

We examined incidental learning of road signs under divided attention in a simulated naturalistic environment. We tested whether word-based versus symbol-based road signs were differentially maintained in working memory by dividing attention during encoding and measuring the effect on long-term memory. Participants in a lab watched a video from the point of view of a car driving the streets of a small town. Participants were instructed to indicate whether passing road signs in the video were on the left or right side of the street while either singing the Star-Spangled Banner (phonological divided attention) or describing familiar locations (visuospatial divided attention). For purposes of analysis, road signs were categorized as word signs if they contained words (e.g., a STOP sign) or as symbol signs if they contained illustrations or symbols (e.g., a pedestrian crosswalk sign). A surprise free recall test of the road signs indicated greater recall for word signs than symbol signs, and greater recall of signs for the phonological divided attention group than the visuospatial divided attention group. Critically, the proportion of correct recall of symbol signs was significantly lower for the visuospatial divided attention group than the phonological divided attention group, p = .02, d = 0.63, but recall for word signs was not significantly different between phonological and visuospatial groups, p = .09, d = 0.44. Results supported the hypothesis that visuospatial information—but not phonological information—is stored in working memory in a simulated naturalistic environment that involved incidental learning.

scholarly journals Utjecaj podizanja trajnih naselja i uzgoja žitarica na razvoj putnih komunikacija / The impact of permanent settlements and grain cultivation on the development of road communications

2017 ◽  
pp. 32-42
Author(s):  
Dženan Brigić
Keyword(s):  
Communication Network ◽  
Roman Period ◽  
Direct Impact ◽  
Neolithic Period ◽  
Community Members ◽  
Communication Development ◽  
The Road ◽  
Long Time ◽  
On The Road ◽  
The Impact

The transformation of hunter-gatherer society, who lived as nomads for a  very long time, largely influenced the development of road communication. These communities now established permanent settlements, especially in arable lands, and had a somewhat lifestyle than before. The cultivation of grains  and domestication of animals meant that people had no more need for migration and the search for better locations, instead they started setting up their  homes in the proximity to other community members, thereby forming the  first Neolithic settlements. By forming the settlements appeared the need to  establish a communication with other communities in the territory of present-day Balkans and wider, usually for the purpose of trade of certain goods,  which had a direct impact on the road communication development that laid  foundations for the development of the roads in the Roman period. Several  such settlements are known in the territory of present-day Bosnia that maintained continuity and tradition as well as road communications from the  Neolithic period up to the Roman period, i.e. Roman governor Publius Cornelius Dolabella, under whose governorship the widest road communication  network was built in the territory of the province of Dalmatia.     

scholarly journals Trailing back from quasi decentralisation to centralisation. Municipal reform in Hungary

2020 ◽  
Vol 14 ◽  
pp. 117-137
Author(s):  
László Kákai
Keyword(s):  
Spatial Distribution ◽  
Public Administration ◽  
Service Provision ◽  
Point Of View ◽  
Direct Impact ◽  
Municipal Reform ◽  
Distribution Of Power ◽  
State Organization ◽  
Centralization And Decentralization

Trailing back from quasi decentralisation to centralisation. Municipal reform in Hungary It is very difficult to group countries and state structures according to the extent of their decentralization or the model they follow in the spatial distribution of power. The bounds of responsibility of local government and the state, the distribution of the roles and tasks between the two stakeholders and the question of centralization and decentralization are issues regularly debated in recent years and today. This topic is not merely a public administration, financial or state organization issue since these decisions have a direct impact on citizens’ lives through public services. In my study I wish to introduce this process via Hungary’s example. I also examine how and what those concerned by the financial and political changes, i.e. the population perceived of this most important structural transformation of the period since the transition in 1989. Can it be verified from the consumers’ point of view that the transformation of the local municipal system improves the quality of service provision?

scholarly journals Determination of ASI and THIV parameters based on the results of experimental and numerical research in relation to EU standards

2021 ◽  
Vol 338 ◽  
pp. 01025
Author(s):  
Michał Stopel
Keyword(s):  
Experimental Tests ◽  
Severity Index ◽  
Point Of View ◽  
The Finite Element Method ◽  
Safety Level ◽  
The Road ◽  
Road Sign ◽  
Numerical Research ◽  
Python Programming

Determining the values of ASI (Acceleration Severity Index) and THIV (Theoretical Head Impact Velocity) parameters during tests allows you to assign an appropriate class for a given type of object to determine the safety level and to give the CE marking. The paper presents the methodology for determining these parameters based on the EN 1317-1 and EN 12767 standards. The paper also presents a tool created with the use of the Python programming language, which, based on the results of experimental tests or the results of numerical calculations, allows to determine the ASI and THIV values. The values of key parameters from the point of view of normative tests were calculated based on the results of experimental tests of the road sign supporting mast and numerical analysis carried out for the same case using the Finite Element Method and LS-Dyna software, following the EN 12767 standard.

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