scholarly journals A Study in Physical and Mechanical Properties of Hemp Fibres

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Asim Shahzad
Keyword(s):  
Mechanical Properties ◽  
Composite Materials ◽  
Moisture Content ◽  
Interfacial Strength ◽  
Physical And Mechanical Properties ◽  
High Moisture Content ◽  
High Moisture ◽  
Fibre Properties ◽  
Hemp Fibres ◽  
Fibre Matrix

This paper presents the results of the experiments undertaken to evaluate various physical and mechanical properties of hemp fibres. The study of these properties is vital for comparison with similar properties of synthetic fibres and for assessing hemp fibres’ suitability for use as reinforcement in composite materials. The properties of hemp fibres were found to be good enough to be used as reinforcement in composite materials. However, the issues of relatively high moisture content of fibres, variability in fibre properties, and relatively poor fibre/matrix interfacial strength were identified as factors that can reduce the efficiency with which these fibres can be utilised.

THE IMPACT OF CLIMATE PARAMETERS ON THE SURFACE OF BUILDINGS’ WALLS

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Ruta Miniotaite
Keyword(s):  
Moisture Content ◽  
Flow Rate ◽  
Paint Film ◽  
Water Flow Rate ◽  
Physical And Mechanical Properties ◽  
High Water ◽  
Vapor Flow ◽  
High Moisture Content ◽  
High Moisture ◽  
The Impact

The durability of surface layers of enclosures (outside walls of buildings) is highly influenced by stresses occurring in the plane of contact between finishing materials and that of the enclosure. Damage to external walls depends on a high moisture content, which in turn depends on high water absorption during driving rains. One example of such damage is damage due to direct water penetration in homogeneous walls. The other negative effects of a high moisture content are impaired heat insulation and accelerated degradation. This article investigates the external layer of walls and the durability of different paints. In case of bi-laminar system “paint film-the wall being painted” two opposite processes take place: the water flow rate from the outside towards the wall, and the water vapor flow rate of the wall to the outside. The optimum selection of paint is necessary. An investigation of the durability of wall surface paints in a climatic chamber is instructive only after intermediate investigations and measurements of the substrates’ physical and mechanical properties that aid in predetermining durability. The influence of moisture deformations upon degradation of coatings depends on the porosity of surface materials being coated, and on the origin and macrostructure of the coating.

scholarly journals STUDY OF PERFORMANCE INDICATORS OF POTATO HARVESTING MACHINES WITH MODERNIZED WORKING BODIES

2021 ◽  
pp. 112-119
Author(s):  
Д.В. ЕВТЕХОВ ◽  
Р.В. БЕЗНОСЮК ◽  
С.Т. КОДИРОВ ◽  
Г.К. РЕМБАЛОВИЧ ◽  
Н.С. ЖБАНОВ
Keyword(s):  
Mechanical Properties ◽  
Composite Materials ◽  
Moisture Content ◽  
Performance Indicators ◽  
Physical And Mechanical Properties ◽  
Climatic Conditions ◽  
Polymer Materials ◽  
Dynamic Loads ◽  
Comparative Performance ◽  
Working Bodies

Проблема и цель. В процессе уборки картофеля меняются почвенно-климатические условия, урожайность, свойства убираемых клубней и поэтому уборочный комплекс должен гибко реагировать на эти изменения. Это предполагает не только своевременную настройку рабочих органов, но и более широкие возможности современных картофелеуборочных машин. Цель – совершенствование картофелеуборочных машин на основе применения полимерных и композиционных материалов. Методология. Появление в бункере комбайна клубней с повреждениями, ушибами (потемнение мякоти) свидетельствует о значительных динамических нагрузках рабочих органов. Предлагаемый сепарирующий элеватор имеет гибкие композиционные прутки, которые взаимодействуют с обрезиненными роликами-интенсификаторами и при движении образуют волнообразную, постоянно меняющуюся поверхность. При поступлении картофельного вороха гибкие композиционные прутки прогибаются, причем чем больше масса поступающего картофельного вороха, тем больше величина прогиба прутков. При изменении почвенно-климатических условий значительная нагрузка приходится на органы выносной сепарации, поэтому увеличение производительности и снижение повреждений клубней является важной задачей. Для повышения эффективности работы продольной прямоточной пальчиковой горки был предложен многокулачковый встряхиватель с регулируемой частотой и амплитудой воздействия. Благодаря колебательным воздействиям полотна пальчиковой горки картофель приобретает дополнительную подвижность, что позволяет более полно использовать различия физико-механических свойств клубней и примесей. Результаты. Применение сепарирующего элеватора с композиционными прутками увеличило сепарирующую способность картофелекопателя на суглинке нормальной влажности (22 %) и снизило повреждения клубней на 2,6 %. Сравнительные показатели качества работы комбайна Grimme DR-1500, оборудованного модернизированной горкой с многокулачковым всряхивателем и серийного комбайна Grimme DR-1500 соответственно составили: полнота уборки – 97,3 % и 95,8 %; полнота выделения примесей – 94,1% и 86,8 %; процент повреждений клубней –2,47 % и 3,15 %. Заключение. Увеличение интенсивности сепарации на рабочих органах из композиционных и полимерных материалов позволяет увеличить производительность картофелеуборочных машин. Problem and purpose. In the process of harvesting potatoes, the soil and climatic conditions change, the yield properties of the harvested tubers, and therefore the harvesting complex must respond fexibly to these changes. This presupposes not only the timely adjustment of the working bodies, but also the wider possibilities of modern potato harvesters. The goal is to improve potato harvesters based on the use of polymer and composite materials. Methodology. The appearance of tubers with injuries in the bunker of the combine with bruises (darkening of the pulp) indicates signifcant dynamic loads of the working organs. The proposed separating elevator has fexible composite rods, which interact with rubberized intensifer rollers and, when moving, form a wavy, constantly changing surface. When the potato heap arrives, the fexible composite rods bend, and the greater the mass of the heap, the greater the defection. With a change in soil and climatic conditions, a signifcant load falls on the external separation organs, therefore, increasing productivity and reducing damage to tubers is an important task. To increase the efciency of the longitudinal direct-fow hedgehog slide, a multi-cam shaker with an adjustable frequency and amplitude of action was proposed. Owing to the vibrational efects of the hedgehog slider, the potato acquires additional mobility, which allows more full use of the diferences in the physical and mechanical properties of tubers and impurities. Results. The use of a separating elevator with composite rods increased the separating capacity of a potato digger on loam of normal moisture content (22%) and reduced damage to tubers by 2.6%. Comparative performance indicators of the Grimme DR-1500 combine equipped with a modernized slide with a multi-cam shaker and the Grimme DR-1500 serial combine, respectively, were: completeness of cleaning –97.3% and 95.8%; completeness of separation of impurities – 94.1% and 86.8%; percentage of damage to tubers –2.47% and 3.15%. Conclusion. An increase in the intensity of separation on working bodies made of composite and polymer materials allows increasing the productivity of potato harvesters.

Influence of Moisture Content on Physicomechanical Properties, Starch-Protein Microstructure and Fractal Parameter of Oat Groats

2018 ◽  
Vol 14 (5-6) ◽  
Author(s):  
Nan Zhao ◽  
Bo-wen Li ◽  
Nan Fu ◽  
Dong Li ◽  
Li-jun Wang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Moisture Content ◽  
Physical Properties ◽  
Granule Size ◽  
Physicomechanical Properties ◽  
Heuristic Methods ◽  
High Moisture Content ◽  
High Moisture ◽  
Fractal Parameter ◽  
Contact Points

AbstractThis study was performed to investigate the influence of moisture content on physicomechanical properties, starch-protein microstructure and fractal parameter of oat groats. Selected physical properties were determined as a function of moisture content. The results showed that moisture content had a significant effect on these characteristics. Majority of physical properties increased linearly with moisture content ranged from 11.8 % to 27.0 %, while mechanical properties decreased nonlinearly as third power function in the above range. Moreover, the increasing granule size, less gaps and more contact points can be observed in the microstructure of starch-protein network with high moisture. Meanwhile, high moisture content also resulted in that fractal parameter of oat section increased from 2.6891 to 2.8001 significantly. These moisture-dependent characteristics are useful in further study of oat groats and the heuristic methods used in this study may be extrapolated to other varieties of cereal.

Drying kinetics of processed natural coffee with high moisture content

2017 ◽  
Vol 12 (3) ◽  
pp. 400 ◽  
Author(s):  
Valdiney Cambuy Siqueira ◽  
Flávio Meira Borém ◽  
Guilherme Euripedes Alves ◽  
Eder Pedroza Isquierdo ◽  
Afonso Celso Ferreira Pinto ◽  
...  
Keyword(s):  
Moisture Content ◽  
Drying Kinetics ◽  
High Moisture Content ◽  
High Moisture ◽  
Kinetics Of

Objetivou-se, com o presente trabalho, propor um novo método de processamento e secagem, assim como avaliar o comportamento dos grãos submetidos a este processo, por meio da taxa de redução de água e do ajuste de diferentes modelos matemáticos aos dados experimentais da secagem. Os frutos colhidos no estágio maduro foram divididos em três lotes. O primeiro foi seco continuamente à temperatura de 40±1 °C. O segundo consiste na secagem do café natural até os teores de água de 0,56±0,02, 0,41±0,02, 0,28±0,02 e 0,20±0,02 decimal (base seca, b.s.), seguido de beneficiamento e secagem contínua nas temperaturas de 35±1 ºC e 40±1 ºC. O terceiro lote correspondeu à secagem contínua do café descascado e desmucilado na temperatura de 40±1 °C. Em todos os lotes, a secagem foi encerrada quando os grãos atingiram o teor de água de 0,12±0,05 (b.s.). Aos dados experimentais da secagem foram ajustados dez modelos matemáticos utilizados para representação da secagem dos produtos agrícolas. Além da representação da cinética de secagem foi avaliada a taxa de redução de água dos grãos. Conclui-se que a taxa de redução de água é maior para a temperatura de secagem de 40±1 °C, especialmente para maiores teores de água. O tempo total de secagem do café beneficiado com alto teor de água é expressivamente reduzido, quando comparado ao tempo de secagem completa do café natural. O modelo de Midilli descreve satisfatoriamente a cinética de secagem do café beneficiado.

scholarly journals Physical and Mechanical Properties of Natural Leaf Fiber-Reinforced Epoxy Polyester Composites

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1369
Author(s):  
Sanjeev Kumar ◽  
Lalta Prasad ◽  
Vinay Kumar Patel ◽  
Virendra Kumar ◽  
Anil Kumar ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Composite Materials ◽  
Synthetic Fibre ◽  
Low Cost ◽  
Fibre Length ◽  
Physical And Mechanical Properties ◽  
Natural Fibres ◽  
Risk Environment ◽  
Insulation Property ◽  
Natural Leaf

In recent times, demand for light weight and high strength materials fabricated from natural fibres has increased tremendously. The use of natural fibres has rapidly increased due to their high availability, low density, and renewable capability over synthetic fibre. Natural leaf fibres are easy to extract from the plant (retting process is easy), which offers high stiffness, less energy consumption, less health risk, environment friendly, and better insulation property than the synthetic fibre-based composite. Natural leaf fibre composites have low machining wear with low cost and excellent performance in engineering applications, and hence established as superior reinforcing materials compared to other plant fibres. In this review, the physical and mechanical properties of different natural leaf fibre-based composites are addressed. The influences of fibre loading and fibre length on mechanical properties are discussed for different matrices-based composite materials. The surface modifications of natural fibre also play a crucial role in improving physical and mechanical properties regarding composite materials due to improved fibre/matrix adhesion. Additionally, the present review also deals with the effect of silane-treated leaf fibre-reinforced thermoset composite, which play an important role in enhancing the mechanical and physical properties of the composites.

scholarly journals Effect of Structural Differences on the Mechanical Properties of 3D Integrated Woven Spacer Sandwich Composites

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4284
Author(s):  
Lvtao Zhu ◽  
Mahfuz Bin Rahman ◽  
Zhenxing Wang
Keyword(s):  
Mechanical Properties ◽  
Composite Materials ◽  
Three Dimensional ◽  
Sheet Thickness ◽  
Physical And Mechanical Properties ◽  
Sandwich Composites ◽  
Computed Tomography Images ◽  
And Performance ◽  
Industrial Textiles ◽  
Load Conditions

Three-dimensional integrated woven spacer sandwich composites have been widely used as industrial textiles for many applications due to their superior physical and mechanical properties. In this research, 3D integrated woven spacer sandwich composites of five different specifications were produced, and the mechanical properties and performance were investigated under different load conditions. XR-CT (X-ray computed tomography) images were employed to visualize the microstructural details and analyze the fracture morphologies of fractured specimens under different load conditions. In addition, the effects of warp and weft direction, face sheet thickness, and core pile height on the mechanical properties and performance of the composite materials were analyzed. This investigation can provide significant guidance to help determine the structure of composite materials and design new products according to the required mechanical properties.

Optimization of drying of low-grade coal with high moisture content using a disc dryer

2014 ◽  
Vol 124 ◽  
pp. 267-274 ◽  
Author(s):  
Seung-Hyun Moon ◽  
In-Soo Ryu ◽  
Seung-Jae Lee ◽  
Tae-In Ohm
Keyword(s):  
Moisture Content ◽  
Low Grade ◽  
High Moisture Content ◽  
High Moisture
Sign in / Sign up

Export Citation Format

Share Document