scholarly journals The Effect of Resins on Rheological and ageing Characteristics of Bitumen for Pavement

2019 ◽  
Vol 258 ◽  
pp. 01004
Author(s):  
Madi Hermadi ◽  
Willy Pravianto
Keyword(s):  
Ageing Process ◽  
Rheological Characteristics ◽  
Natural Rock ◽  
Complex Shear ◽  
Petroleum Bitumen ◽  
New Type ◽  
Normal Ageing ◽  
Temperature Levels ◽  
Materials Used

Bitumen consists of thousands of hydrocarbon molecule types with each molecule contributes to the overall bitumen characteristics. Therefore, it is important to identify the influence of each chemical component of bitumen that altogether constructs the bitumen characteristics. This is likely to be completed by evaluating and modifying bitumen components to produce a new type of bitumen with better characteristics. The realistic way to do this is by analysing it in groups or fractions; one group or fraction comprises bitumen molecules with similar characteristics. This paper aims to address this issue by describing the effect of resins on rheological characteristics of bitumen at various ageing process stages. The materials used in this study were Buton rock asphalt or natural rock asphalt from Buton Island in Indonesia which was from Lawele region and petroleum bitumen penetration grade 80/100 from a refinery in Kemaman Malaysia. The materials were tested to identify their charactheristics and the resins components were also extracted and tested with Corbett method. Each extracted resin (from Buton rock asphalt bitumen and petroleum bitumen) was blended in proportions of 0%, 5%, and 10% with the Kemaman petroleum bitumen as a bitumen medium. The blended bitumen samples were also tested for their rheological characteristics using Dynamic Shear Rheometer. Each sample was tested at five different temperature levels (46°C, 52°C, 58°C, 64°C and 70°C) and at un-aged, artificial short-term aged (RTFOT-aged), and artificial long-term aged (PAV-aged) conditions. The results indicated that the source of resins had a significant value of 0.065 or larger than the 0.05 critical point value. There was no difference in the effect of the experiments using either Buton rock asphalt or petroleum bitumen on the complex shear modulus G*. At fresh condition, there was no effect of adding resins on the bitumen rheological characteristics except for the elastic modulus (G’). However, the effect increased over the RTFOT-ageing and PAV-aging level because of the normal ageing process.

scholarly journals Current and New Approaches to Predict the Deflections of One-Way Flexural Members with a Focus on Composite Steel Deck Slabs Voided by Circular Tubes

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 421
Author(s):  
Chang-Hwan Lee ◽  
Iman Mansouri ◽  
Jaehoon Bae ◽  
Jaeho Ryu
Keyword(s):  
Structural Function ◽  
Flexural Members ◽  
Long Span ◽  
Deck Slabs ◽  
New Type ◽  
New Perspective ◽  
Flexural Tests ◽  
Prediction Approach ◽  
Steel Deck

A new type of composite voided slab, the TUBEDECK (TD), which utilizes the structural function of profiled steel decks, has recently been proposed. Previous studies have confirmed that the flexural strength of TD slabs can be calculated based on the full composite contribution of the steel deck, but for long-span flexural members, the deflection serviceability requirement is often dominant. Herein, we derived a novel deflection prediction approach using the results of flexural tests on slab specimens, focusing on TD slabs. First, deflection prediction based on modifications of the current code was proposed. Results revealed that TD slabs exhibited smaller long-term deflections and at least 10% longer maximum span lengths than solid slabs, indicating their greater efficiency. Second, a novel rational method was derived for predicting deflections without computing the effective moment of inertia. The ultimate deflections predicted by the proposed method correlated closely with the deflection under maximum bending moments. To calculate immediate deflections, variation functions for the concrete strain at the extreme compression fiber and neutral axis depth were assumed with predictions in good agreement with experiments. The proposed procedure has important implications in highlighting a new perspective on the deflection prediction of reinforced concrete and composite flexural members.

Preparation of Conductive Nanosilver Ink and its Application on RFID Tags

2014 ◽  
Vol 904 ◽  
pp. 121-125 ◽  
Author(s):  
Ji Lan Fu ◽  
Ya Ling Li ◽  
Li Xin Mo ◽  
Yu Wang ◽  
Jun Ran ◽  
...  
Keyword(s):  
Flexible Electronics ◽  
Screen Printing ◽  
Surface Resistance ◽  
Large Scale ◽  
Printed Electronics ◽  
Silver Content ◽  
Rfid Tags ◽  
Rheological Characteristics ◽  
Conductive Ink ◽  
New Type

The recent dramatic progress in the printed electronics and flexible electronics, due to the universality of the substrates including the foldable and stretchable substrates, has opened a new prospect in the field of future electronics. In this paper, silver nanospheres in large-scale are synthesized, the nanosilver ink with 63.88% silver content are prepared and a new type of highly conductive and far identify distance RFID tags are manufactured. Especially there are no resin and other additives containing in our conductive ink which satisfy the rheological characteristics and process of screen printing. The tags exhibit the best radiation performance own to there is no high temperature sintering in need. The surface resistance of the tags could be 80 mΩ/, and the identify distance reach to 6.0m. Keywords:silver nanoparticles, conductive ink, RFID tags

scholarly journals Response of the temperate coral <i>Cladocora caespitosa</i> to mid- and long-term exposure to <i>p</i>CO<sub>2</sub> and temperature levels projected for the year 2100 AD

2010 ◽  
Vol 7 (1) ◽  
pp. 289-300 ◽  
Author(s):  
R. Rodolfo-Metalpa ◽  
S. Martin ◽  
C. Ferrier-Pagès ◽  
J.-P. Gattuso
Keyword(s):  
Slow Growth ◽  
Elevated Pco2 ◽  
Saturation State ◽  
Co2 Partial Pressure ◽  
Cladocora Caespitosa ◽  
Temperate Coral ◽  
Predominant Factor ◽  
Zooxanthellate Coral ◽  
Temperature Levels

Abstract. Atmospheric CO2 partial pressure (pCO2) is expected to increase to 700 μatm or more by the end of the present century. Anthropogenic CO2 is absorbed by the oceans, leading to decreases in pH and the CaCO3 saturation state (Ω) of the seawater. Elevated pCO2 was shown to drastically decrease calcification rates in tropical zooxanthellate corals. Here we show, using the Mediterranean zooxanthellate coral Cladocora caespitosa, that an increase in pCO2, in the range predicted for 2100, does not reduce its calcification rate. Therefore, the conventional belief that calcification rates will be affected by ocean acidification may not be widespread in temperate corals. Seasonal change in temperature is the predominant factor controlling photosynthesis, respiration, calcification and symbiont density. An increase in pCO2, alone or in combination with elevated temperature, had no significant effect on photosynthesis, photosynthetic efficiency and calcification. The lack of sensitivity C. caespitosa to elevated pCO2 might be due to its slow growth rates, which seem to be more dependent on temperature than on the saturation state of calcium carbonate in the range projected for the end of the century.

Solvent-Based Polymer Swelling Characterization for the Development of the Nano/Micro-Particle Polymer Composite MEMS Corrosion Sensor

2014 ◽  
Author(s):  
Feng Pan ◽  
Abdoul Kader Maiga ◽  
Po-Hao Adam Huang
Keyword(s):  
Reaction Products ◽  
Material Transport ◽  
Sensing Element ◽  
Micro Electro Mechanical Systems ◽  
Polymer Swelling ◽  
Corrosion Sensor ◽  
Mems Technology ◽  
New Type ◽  
Oxide Removal

The concept of using Micro-Electro-Mechanical Systems (MEMS) for in-situ corrosion sensing and for long-term applications has been proposed and is currently under development by our research lab. This is a new type of sensing using MEMS technology and, to the knowledge of our team, has not been explored previously. The MEMS corrosion sensor is based on the oxidation of metal nano/micro-particle embedded in elastomeric polymer to form a composite sensing element. The polymer controls the diffusion into and out of the sensor while the corrosion of the metal particles inhibits electrical conduction which is used as the detection signal. The work presented here is based on part of the methods developed for the removal of native and process-induced metal oxides. A major aspect is the study of the swelling dynamics of the polymer matrix (polydimethylsiloxane, PDMS) intended for enhancing material transport of etchants into and reaction products out of the composite during oxide removal. More specifically, the characterization of the swelling of copper particles-PDMS composite samples in liquid solvent baths is presented.

scholarly journals Analysis of requirements for modern finishing materials in interior solutions for inpatient facility ward units

2021 ◽  
Vol 284 ◽  
pp. 05001
Author(s):  
Alevtina Balakina ◽  
Yury Lempl
Keyword(s):  
Practical Experience ◽  
Interior Decoration ◽  
Term Care ◽  
Normative Documents ◽  
Inpatient Facility ◽  
The Russian Federation ◽  
Materials Used ◽  
Capital Construction

This article is devoted to the detailed analysis of modern requirements for finishing materials, used in the interiors of inpatient facility ward units. The authors have studied a number of regulatory normative documents acting in the territory of the Russian Federation and analyzed the practical experience of interior decoration of ward units at the health care capital construction facilities. The authors highlight and describe the main requirements for the finishing materials for the inpatient facility ward units and point out the peculiarities of solutions in the interiors. A classification of modern finishing materials (with an indication of their technical characteristics) used in the decoration of interiors of long-term care units is made on the basis of the practical experience studied by the authors taking into account the functional purpose of the premises as well as the variants of visual design of interiors of inpatient facility ward units.

scholarly journals Long-Term Behavior of Coarse-Grained Rockfill Material and Their Constitutive Modeling

2021 ◽  
Author(s):  
Erich Bauer
Keyword(s):  
Mechanical Response ◽  
Coarse Grained ◽  
Geological Condition ◽  
Dam Foundation ◽  
Solid Hardness ◽  
Rockfill Materials ◽  
Materials Used ◽  
Creep And Stress Relaxation ◽  
Long Term Behavior

For the long-term behavior and safety assessment of rockfill dams, not only the shape of the dam body, the loading history, the geological condition of the dam foundation and abutments, the assessment of possible seismic hazards and seepage events caused by defects of the sealing are important, but also the time dependent mechanical behavior of the dam materials used can be of significant influence. In this paper a novel hypoplastic constitutive model for moisture sensitive, coarse-grained rockfill materials is presented. In the constitutive equations, the so-called solid hardness is a key parameter to reflect the influence of the state of weathering on the mechanical response. With respect to the evolution equation for the solid hardness, creep and stress relaxation can be modeled for dry and wet states of the material in a unified manner. The performance of the model is demonstrated by comparing the numerical simulation with experimental data.

scholarly journals Sustainable activities in manufacturing enterprises: Consumers’ expectations

Upravlenets ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 91-101
Author(s):  
Patrícia Jánošová
Keyword(s):  
Slovak Republic ◽  
Specific Area ◽  
Environmental Indicators ◽  
Market Demand ◽  
Bottom Line ◽  
Manufacturing Enterprises ◽  
Survey Results ◽  
Materials Used

Generating profit is one of the primary reasons behind the establishment and functioning of any enterprise that predetermines its behavior, inter alia, in the context of sustainability. Manufacturing enterprises are a specific area in terms of sustainability, as they have a great impact on social and environmental indicators. The paper analyses the issues of sustainable production in the Slovak Republic. The methodological basis of the study is the triple-bottom line concept. The methods used in the paper are analysis, synthesis and comparison. Within the framework of the research, the author has conducted two surveys in the form of open-ended questions. The first part is dedicated to consumers’ evaluation of the production activity of manufacturing enterprises. Consumers as stakeholders of an enterprise have a significant influence on its activities due to the fact that they create market demand. The survey results show that the main methods for stimulating consumers’ sustainable behaviour are the use of compostable packaging and abandoning chemical sprays. The second part is an overview of barriers and problems at enterprises that prevent consumers in the Slovak Republic from transitioning to a sustainable lifestyle. Among them are excessive plastic packaging and high prices for eco-products. The presented activities determine the direction for managers how to lead enterprises to sustainability in the market. The most significant findings from the surveys point to the excessive and reckless use of plastic by manufacturing enterprises. Consumers demand that managers make rational decisions about the origin, quantity and quality of materials used in production, including the long-term consequences and environmental impact of materials.

Effect of reintroduced manual mowing on biodiversity in abandoned fen meadows

Biologia ◽  
2015 ◽  
Vol 70 (1) ◽  
Author(s):  
Jakub Horak ◽  
Lenka Safarova
Keyword(s):  
Restoration Ecology ◽  
Conservation Value ◽  
High Conservation ◽  
New Type ◽  
Surrounding Landscape ◽  
Flower Visiting ◽  
Short Time ◽  
Positive Effect ◽  
Insect Group

AbstractWetlands have recently become of high environmental interest. The restoration effects on habitats like fens are one of the main topics of recent restoration ecology, especially due to their interconnection with other ecosystems. We studied the manual mowing effect on abandoned fen using the response of three study taxa: diurnal butterflies, flower-visiting beetles and vascular plants. Our results showed that butterflies seems to be quickly-responding indicator taxon for evaluation and that restored management had a positive effect on both species richness and composition of this insect group. The results indicated that the manual mowing effect could be rapid. In comparison with the surrounding landscape, we found that: (i) the manually mowed site was most similar to strictly protected area, (ii) some species of high conservation value could reach higher abundance in restored than protected site, and (iii) manual mowing could bring a new type of habitat (i.e., spatial heterogeneity) compared to the other management types (abandonment, conservation and agri-environmental mowing). The main implication seems to be optimistic for practice: The manual mowing of long-term abandoned fen is leading to the creation of habitat with high conservation value in a relatively short time.

scholarly journals Material Science in Cervical Total Disc Replacement

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Martin H. Pham ◽  
Vivek A. Mehta ◽  
Alexander Tuchman ◽  
Patrick C. Hsieh
Keyword(s):  
Biological Effects ◽  
Total Disc Replacement ◽  
The United States ◽  
Disc Replacement ◽  
Disc Space ◽  
Prosthetic Devices ◽  
Cervical Total Disc Replacement ◽  
Materials Used ◽  
Cobalt Chrome

Current cervical total disc replacement (TDR) designs incorporate a variety of different biomaterials including polyethylene, stainless steel, titanium (Ti), and cobalt-chrome (CoCr). These materials are most important in their utilization as bearing surfaces which allow for articular motion at the disc space. Long-term biological effects of implanted materials include wear debris, host inflammatory immune reactions, and osteolysis resulting in implant failure. We review here the most common materials used in cervical TDR prosthetic devices, examine their bearing surfaces, describe the construction of the seven current cervical TDR devices that are approved for use in the United States, and discuss known adverse biological effects associated with long-term implantation of these materials. It is important to appreciate and understand the variety of biomaterials available in the design and construction of these prosthetics and the considerations which guide their implementation.

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