scholarly journals THE EFFECT OF A PLASTICIZING ADMIXTURE ON THE PROPERTIES OF HARDENED CONCRETE / PLASTIFIKATORIAUS POVEIKIS SUKIETĖJUSIO BETONO SAVYBĖMS

2012 ◽  
Vol 4 (4) ◽  
pp. 289-293
Author(s):  
Anastasija Abasova ◽  
Džigita Nagrockienė
Keyword(s):  
Matrix Material ◽  
Ultrasonic Pulse ◽  
Raw Material ◽  
Hardened Concrete ◽  
Test Results ◽  
Fundamental Properties ◽  
Additive Increase ◽  
Mixing Matrix ◽  
The Impact ◽  
Plasticizing Admixture

Concrete is material obtained mixing matrix material, coarse and small aggregates and water along with additives acquiring necessary properties of hardening. The quality and properties of raw material used for manufacturing concrete, V/C ratio and the uniformity of the compaction of the mixture lead to the fundamental properties of concrete. The compressive strength of concrete is one of the most important properties of concrete. The article deals with the impact of plasticizers on the structural properties of concrete choosing an optimal content of additives. Concrete plasticizers increasing the content of additive increase the strength of samples, the density and ultrasonic pulse of velocity and decrease absorption. Test results have revealed that a plasticizing admixture under dosing or overdosing can reduce the properties of concrete. Santrauka Betonas – medžiaga, kuri sumaišius rišamąją medžiagą, stambiuosius ir smulkiuosius užpildus, vandenį bei pridėjus priedų, reikiamų savybių įgyja kietėdama. Betonui gaminti naudojamų žaliavų kokybė ir savybės, V/C santykis, mišinio sutankinimo vienodumas lemia pagrindines betono savybes. Betono gniuždymo stipris yra viena iš svarbiausių betono savybių. Straipsnyje nagrinėjamas plastifikatoriaus poveikis betono savybėms, parenkamas optimalus jo kiekis. Atlikus betono savybių tyrimus su skirtingais kiekiais plastifikatoriaus, nustatyta, kad betone didinant plastifikatoriaus kiekį, didėja bandinių gniuždymo stipris, tankis ir ultragarso impulso sklidimo greitis, o įmirkis mažėja. Pagal gautus tyrimo rezultatus nustatyta, kad nepakankamas plastifikatoriaus kiekis arba jo perdozavimas gali pabloginti betono savybes.

scholarly journals INCREASED PRODUCTIVITY OF LIQUID SMOKE THROUGH FAST THAWING WITH REFRIGERATION SYSTEMS AT LOW AIR TEMPERATURE

2021 ◽  
pp. 1-6
Author(s):  
Baiti Hidayati ◽  
Riman Sipahutar ◽  
Irwin Bizzy ◽  
Muhammad Faizal
Keyword(s):  
Air Temperature ◽  
Palm Kernel ◽  
Chemical Compounds ◽  
Raw Material ◽  
Condensation Process ◽  
Test Results ◽  
Palm Kernel Shell ◽  
Liquid Smoke ◽  
Cabin Temperature ◽  
The Impact

Liquid smoke increased in demand by the community because it is made from environmentally friendly waste can directly reduce the impact of environmental pollution. The smoke condensing process that is carried out conventionally using water can be continuously replaced using a refrigeration system, the smoke condensation process can be carried out using controlled low-temperature air, this can minimize machine space and energy. In this study, an analysis of variations in air temperature will be carried out to maximize the productivity of liquid smoke. The raw material for palm kernel shell is -4 + 5 mesh with cabin temperature variations of 15-10°C, 10-5°C, and 5-0°C and pyrolysis temperature of 300-400°C. Based on the research results obtained maximum results at a temperature of 5-0°C with 23.6% liquid smoke, 3.7% tar, 63.8% charcoal, and 8.9% gas. Based on the test results of chemical compounds, liquid smoke has an average phenol value of 56.59%. The lower the air temperature used to condense the smoke, the maximum liquid smoke will be and the less gas escapes to the air. It can directly reduce air pollution in the process of making liquid smoke.

scholarly journals DESIGN AND MANUFACTURE OF SKATEBOARD FROM BANANA STEM

2019 ◽  
Vol 3 (2) ◽  
pp. 109
Author(s):  
Achmad Jusuf Zulfikar ◽  
Bobby Umroh ◽  
Muhammad Yusuf Rahmansyah Siahaan
Keyword(s):  
Flexural Strength ◽  
Matrix Material ◽  
Composite Fiber ◽  
Raw Material ◽  
Environmental Damage ◽  
Average Value ◽  
The Matrix ◽  
Design And Manufacture ◽  
The Impact ◽  
Banana Stem

A skateboard is a small piece of wood shaped like a surfboard with four wheels attached to it that is used to glide on a certain track. In general, this tool is made using wood material taken from nature and vulnerable to environmental damage issues. In this research, the waste of banana stems will be processed into the main raw material for skateboarding. The type of material chosen is the type of composite material with banana stem waste selected as reinforcement and polyester resin as the matrix material. The purpose of this research is to design and manufacture a skateboard made of composite fiber reinforced banana stem fibers and to test its flexural strength to obtain the characteristics of the material formed. The design was carried out with the help of the 2007 version of Autocad software by following commercial skateboard standards.  Flexural testing was carried out at the Impact and Fracture Research Center laboratory, Faculty of Engineering, University of North Sumatra. Static static testing of polymer composite board specimens from banana stems obtained the average value data for the composition of 5% banana stems is 9.81 MPa, for the composition of 10% banana stems an average of 13.60 MPa, and composition of 15% banana stems the average is 27.20 MPa. 2. The analysis shows that the best composition is 15% of banana stems, with an average flexural strength value of 27.20 MPa. Therefore, the composition used in this study is the composition of 15% reinforcement of banana stems.

PENGKAJIAN KEKUATAN BETON STRUKTUR JEMBATAN PASCA KEBAKARAN

2013 ◽  
Vol 12 (3) ◽  
Author(s):  
Sudarmadi Sudarmadi
Keyword(s):  
Compressive Strength ◽  
Concrete Strength ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Test Results ◽  
Concrete Compressive Strength ◽  
Strength Assessment ◽  
Concrete Testing

In this paper a case study about concrete strength assessment of bridge structure experiencing fire is discussed. Assessment methods include activities of visual inspection, concrete testing by Hammer Test, Ultrasonic Pulse Velocity Test, and Core Test. Then, test results are compared with the requirement of RSNI T-12-2004. Test results show that surface concrete at the location of fire deteriorates so that its quality is decreased into the category of Very Poor with ultrasonic pulse velocity ranges between 1,14 – 1,74 km/s. From test results also it can be known that concrete compressive strength of inner part of bridge pier ranges about 267 – 274 kg/cm2 and concrete compressive strength of beam and plate experiencing fire directly is about 173 kg/cm2 and 159 kg/cm2. It can be concluded that surface concrete strength at the location of fire does not meet the requirement of RSNI T-12-2004. So, repair on surface concrete of pier, beam, and plate at the location of fire is required.

Impact Strength, Flexural Modulus and Wear Rate of PMMA Composites Reinforced by Eggshell Powders

2020 ◽  
Vol 38 (7A) ◽  
pp. 960-966
Author(s):  
Aseel M. Abdullah ◽  
Hussein Jaber ◽  
Hanaa A. Al-Kaisy
Keyword(s):  
Impact Strength ◽  
Wear Rate ◽  
Flexural Modulus ◽  
Matrix Material ◽  
Weight Fraction ◽  
Pure Pmma ◽  
Calcination Process ◽  
The Matrix ◽  
The Impact ◽  
Interface Bond

In the present study, the impact strength, flexural modulus, and wear rate of poly methyl methacrylate (PMMA) with eggshell powder (ESP) composites have been investigated. The PMMA used as a matrix material reinforced with ESP at two different states (including untreated eggshell powder (UTESP) and treated eggshell powder (TESP)). Both UTESP and TESP were mixed with PMMA at different weight fractions ranged from (1-5) wt.%. The results revealed that the mechanical properties of the PMMA/ESP composites were enhanced steadily with increasing eggshell contents. The samples with 5 wt.% of UTESP and TESP additions give the maximum values of impact strength, about twice the value of the pure PMMA sample. The calcination process of eggshells powders gives better properties of the PMMA samples compared with the UTESP at the same weight fraction due to improvements in the interface bond between the matrix and particles. The wear characteristics of the PMMA composites decrease by about 57% with increases the weight fraction of TESP up to 5 wt.%. The flexural modulus values are slightly enhanced by increasing of the ESP contents in the PMMA composites.

Model estimates of the results of diabetes patients using modern glucometers with tri-color technology for displaying test results

2019 ◽  
pp. 81-89
Author(s):  
Larisa Dmitrievna Popovich ◽  
Svetlana Valentinovna Svetlichnaya ◽  
Aleksandr Alekseevich Moiseev
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 1 Diabetes ◽  
Economic Benefits ◽  
Test Results ◽  
Self Monitoring ◽  
Patients With Diabetes ◽  
The Impact

Diabetes – a disease in which the effect of the treatment substantially depends on the patient. Known a study showed that the use of glucometers with the technology of three-color display of test results facilitates self-monitoring of blood sugar and leads to a decrease in glycated hemoglobin (HbAlc). Purpose of the study: to modeling the impact of using of a glucometer with a color-coded display on the clinical outcomes of diabetes mellitus and calculating, the potential economic benefits of reducing the hospitalization rate of patients with diabetes. Material and methods. Based on data from two studies (O. Schnell et al. and M. Baxter et al.) simulation of the reduction in the number of complications with the use of a glucometer with a color indication. In a study by O. Schnell et al. a decrease of HbA1c by 0.69 percent is shown when using the considered type of glucometers, which was the basis of the model. Results. In the model, the use of a glucometer with a color-coded display for type 1 diabetes led to a decrease in the total number of complications by 9.2 thousand over 5 years per a cohort of 40 thousand patients with different initial levels of HbA1c. In a cohort of 40 thousand patients with type 2 diabetes, the simulated number of prevented complications was 1.7 thousand over 5 years. When extrapolating these data to all patients with diabetes included in the federal register of diabetes mellitus (FRD), the number of prevented complications was 55.4 thousand cases for type 1 diabetes and 67.1 thousand cases for type 2 diabetes. The possible economic effect from the use of the device by all patients with a diagnosis of diabetes, which are included in the FRD, estimated at 1.5 billion rubles for a cohort of patients with type 1 diabetes and 5.3 billion rubles for patients with type 2 diabetes. Conclusion. Improving the effectiveness of self-monitoring, which is the result of the use of glucometers with color indicators, can potentially significantly reduce the incidence of complications in diabetes and thereby provide significant economic benefits to society.

scholarly journals The Impact of Filler Geometry on Polylactic Acid-Based Sustainable Polymer Composites

Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 149
Author(s):  
Karol Leluk ◽  
Stanisław Frąckowiak ◽  
Joanna Ludwiczak ◽  
Tomasz Rydzkowski ◽  
Vijay Kumar Thakur
Keyword(s):  
Polymer Composites ◽  
Polylactic Acid ◽  
Matrix Material ◽  
Chemical Properties ◽  
Precipitated Calcium Carbonate ◽  
Cellulose Fibres ◽  
Shape Factors ◽  
Pure Cellulose ◽  
Physico Chemical ◽  
The Impact

Recently, biocomposites have emerged as materials of great interest to the scientists and industry around the globe. Among various polymers, polylactic acid (PLA) is a popular matrix material with high potential for advanced applications. Various particulate materials and nanoparticles have been used as the filler in PLA based matrix. One of the extensively studied filler is cellulose. However, cellulose fibres, due to their hydrophilic nature, are difficult to blend with a hydrophobic polymer matrix. This leads to agglomeration and creates voids, reducing the mechanical strength of the resulting composite. Moreover, the role of the various forms of pure cellulose and its particle shape factors has not been analyzed in most of the current literature. Therefore, in this work, materials of various shapes and shape factors were selected as fillers for the production of polymer composites using Polylactic acid as a matrix to fill this knowledge gap. In particular, pure cellulose fibres (three types with different elongation coefficient) and two mineral nanocomponents: precipitated calcium carbonate and montmorillonite were used. The composites were prepared by a melt blending process using two different levels of fillers: 5% and 30%. Then, the analysis of their thermomechanical and physico-chemical properties was carried out. The obtained results were presented graphically and discussed in terms of their shape and degree of filling.

scholarly journals Functionalization of Enzymatically Treated Apple Pomace from Juice Production by Extrusion Processing

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 485
Author(s):  
Vera Schmid ◽  
Antje Trabert ◽  
Judith (Schäfer) Keller ◽  
Mirko Bunzel ◽  
Heike P. Karbstein ◽  
...  
Keyword(s):  
Water Absorption ◽  
Dietary Fiber ◽  
Water Solubility ◽  
Apple Pomace ◽  
Raw Material ◽  
Food Ingredients ◽  
Insoluble Dietary Fiber ◽  
Extrusion Processing ◽  
The Impact ◽  
Treated Apple

Food by-products can be used as natural and sustainable food ingredients. However, a modification is needed to improve the technofunctional properties according to the specific needs of designated applications. A lab-scale twin-screw extruder was used to process enzymatically treated apple pomace from commercial fruit juice production. To vary the range of the thermomechanical treatment, various screw speeds (200, 600, 1000 min−1), and screw configurations were applied to the raw material. Detailed chemical and functional analyses were performed to develop a comprehensive understanding of the impact of the extrusion processing on apple pomace composition and technofunctional properties as well as structures of individual polymers. Extrusion at moderate thermomechanical conditions increased the water absorption, swelling, and viscosity of the material. An increase in thermomechanical stress resulted in a higher water solubility index, but negatively affected the water absorption index, viscosity, and swelling. Scanning electron microscopy showed an extrusion-processing-related disruption of the cell wall. Dietary fiber analysis revealed an increase of soluble dietary fiber from 12.6 to 17.2 g/100 g dry matter at maximum thermo-mechanical treatment. Dietary fiber polysaccharide analysis demonstrated compositional changes, mainly in the insoluble dietary fiber fraction. In short, pectin polysaccharides seem to be susceptible to thermo-mechanical stress, especially arabinans as neutral side chains of rhamnogalacturonan I.

scholarly journals Effect of Biochar Prepared from Food Waste through Different Thermal Treatment Processes on Crop Growth

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 276
Author(s):  
Hang Jia ◽  
Haoxi Ben ◽  
Fengze Wu
Keyword(s):  
Crop Growth ◽  
Raw Material ◽  
Synthetic Methods ◽  
Thermochemical Conversion ◽  
Growth Trend ◽  
Wheat Growth ◽  
Preparation Methods ◽  
Treatment Processes ◽  
Ft Ir ◽  
The Impact

Biochar is generally accepted and increasingly valued in scientific circles as solid products in the thermochemical conversion of biomass, mainly because of its rich carbon content. The purpose of this research is to investigate the impact of biochar from different sources on wheat growth. In particular, this work focused on the effect of different preparation methods and raw material of biochar on the growth of wheat and aim to find a potential soil substitute that can be used for crop cultivation. Two synthetic methods were evaluated: hydrothermal conversion and pyrolysis. The characterization of biochar was determined to explore the impact of its microstructure on wheat growth. The results show that the yield of biochar produced from high-pressure reactor is significantly higher than that obtained by using microwave reactor. For example, the biochar yield obtained through the former is about six times that of the latter when using steamed bread cooked as biomass raw material. In addition, the growth trend of wheat indicates that biochar has different promoting effects on the growth of wheat in its weight and height. The pyrolyzed carbon is more suitable for wheat growth and is even more effective than soil, indicating that pyrolyzed biochar has more potential to be an alternative soil in the future. Moreover, this research tries to explore the reasons that affect crop growth by characterizing biochar (including scanning electron microscopy (SEM), biofilm electrostatic test (BET) and Fourier transform infrared (FT-IR)). The results indicate that the biochar containing more pits and less hydroxyl functional are more suitable for storing moisture, which is one of the significant factors in the growth of crops. This study provides evidence of the effects of biochar on crop growth, both in terms of microstructure and macroscopic growth trends, which provides significant benefits for biochar to grow crops or plants.

scholarly journals Effects of Urbanization on Ecosystem Services in the Shandong Peninsula Urban Agglomeration, in China: The Case of Weifang City

Urban Science ◽  
2021 ◽  
Vol 5 (3) ◽  
pp. 54
Author(s):  
Yuejuan Yang ◽  
Hao Zhang ◽  
Xinquan Zhao ◽  
Zhizhang Chen ◽  
Aiguo Wang ◽  
...  
Keyword(s):  
Sustainable Development ◽  
Ecosystem Services ◽  
Remote Sensing Data ◽  
Population Data ◽  
Raw Material ◽  
Nutrient Cycle ◽  
The Sustainable Development ◽  
Impact Of Urbanization ◽  
Academy Of Sciences ◽  
The Impact

Ecosystem services are the material basis of economic and social development, and play essential roles in the sustainable development of ecosystems. Urbanization can remarkably alter the provision of ecosystem services. Most studies in this area have focused on densely populated metropolises with poor ecological environments, while comparatively few studies have focused on cities with low ecological pressures. Therefore, to avoid continuing to engage in the repetitive pattern of destroying first and rehabilitating later, quantitative analyses of urbanization and ecosystem services should be carried out in representative cities. In this study, based on partial least squares-discriminant analysis, kernel density estimation, and correlation analysis, we quantitatively evaluated the impact of urbanization on ecosystem services in Weifang city. The Data Center for Resources and Environmental Sciences at the Chinese Academy of Sciences and the Institute of Geographic Sciences and Natural Resources Research provided remote sensing data on land use, the gross domestic production (GDP), population data, and ecosystem services. The results were as follows: (1) The variation in population, GDP, and built-up areas consistently increased throughout the study period, whereas the ecosystem service values (ESVs) decreased; (2) food production, raw material production, nutrient cycle maintenance, and soil conservation were decisive ecosystem services that led to vast reductions in ESVs during the process of urbanization; and (3) the negative correlation coefficient between built-up areas and ecosystem services was greater than that between the population or GDP and ecosystem services, which indicated that the impacts of population and economic urbanization on ecosystem services lagged behind the impact of land urbanization. This study provides references for fully recognizing the ecological effects of urbanization, and make suggestions regarding the application of ecosystem services in sustainable development.

scholarly journals Sustainability of Extraction of Raw Material by a Combination of Mobile and Stationary Mining Machines and Optimization of Machine Life Cycle

2020 ◽  
Vol 12 (24) ◽  
pp. 10454
Author(s):  
Katarína Teplická ◽  
Martin Straka
Keyword(s):  
Life Cycle ◽  
Raw Materials ◽  
Simulation Method ◽  
Raw Material ◽  
Optimal Distribution ◽  
Transport Costs ◽  
Scientific Discussion ◽  
Mining Companies ◽  
Conveyor Belts ◽  
The Impact

This article summarizes the arguments within the scientific discussion on the issue of using mining machines and their life cycle. The main goal of the article is to investigate the impact of a combination of mobile and stationary mining machines and their optimal distribution in the mining process to increase the efficiency of mining and processing of raw materials. The following methods of research were focused on the use of technical indicators for the valuation efficiency of the mining process: a simulation method was used for the distribution of mining machines, comparison analysis was used for the real and past state of mining machines, and a decision tree was used as managerial instrument for optimal alternatives of mining machines. The research empirically confirms and theoretically proves that optimal distribution of mining machines and machine parks is very important for mining companies. The benefit of this research for the mining company was the new location of the machines and the combination of stationary production lines and mobile equipment. The optimal layout of the machines reduced the number of conveyor belts and improved the transfer of limestone processing to mobile devices, saving time, which was reflected in transport costs. The results can be useful for other mining companies seeking to create an optimal machine park.

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