scholarly journals Researching the change in the weight of split oak firewood due to different drying methods

2021 ◽  
Vol 1208 (1) ◽  
pp. 012023
Author(s):  
Amina Gačo
Keyword(s):  
Room Temperature ◽  
Average Weight ◽  
Drying Methods ◽  
Initial Water Content ◽  
Initial Weight ◽  
Average Amount ◽  
Initial Amount ◽  
Initial Water ◽  
Original Weight ◽  
Air Circulation

Abstract In this paper, the influences of stacking methods and drying places of split oak firewood in winter conditions (Quercus cerris) have been experimentally and theoretically investigated, due to the great importance of use in heating with such wood. The research was conducted on a sample of 48 pieces of logs with bark made of freshly cut oak. The logs were obtained by mechanized technology with the help of grafting by a hydraulic splitter and a chainsaw. Each log was measured for a research length of 0.30 m, marked with numbers 1-24. On each log, the weight was measured on a scale of 5 kg with an accuracy of 0.5 grams. Drying of logs was performed in two places. The first drying place was in outdoor conditions, sheltered from the snow and ventilated. The second place was indoors, at approximately constant room temperature. The logs were stacked in a crossed way for better air circulation. They were dried between 15/12/2020 and 15/02/2021, a total of 62 days. The average initial weight of logs dried in the facility was 1130.3 g, in the dried state the average weight was 952.87 g, which represented 84.3% of the original weight. The average initial weight of logs dried in outdoor conditions was 1192.125 g, in the dried state 1076.37 g, which represented 90.29% of the original weight. The average initial water content in the logs dried in the facility was 37.9%, in the dried state it was 27.5%. For logs dried in outdoor conditions, the average initial amount of water was 36.6%, in the dried state the average amount of water was 31.2%.

The physical factors involved in the drying of sultana grapes

1957 ◽  
Vol 8 (5) ◽  
pp. 444 ◽  
Author(s):  
RJL Martin ◽  
GL Stott
Keyword(s):  
Free Water ◽  
Total Loss ◽  
Drying Rate ◽  
Physical Factors ◽  
Initial Water Content ◽  
Initial Water ◽  
Loss Of Weight ◽  
Original Weight ◽  
Drying Rates ◽  
Parenchymal Cells

The various physical factors involved in the drying of sultana grapes have been determined from measurements of drying rate under definite conditions of temperature, humidity, and air flow, in a specially constructed oven. Ninety-five per cent. of weight lost is water, 2 per cent. is carbon dioxide produced at an almost constant rate during drying, and 3 per cent. unassigned loss. Drying occurs in three distinct stages: (1) the grape retains its regular ellipsoidal shape by an elastic contraction of the skin; (2) the skin commences to wrinkle in the range of 20-50 per cent, loss in original weight; (3) the drying rate decreases markedly, beginning when approximately 95 per cent. of total loss of weight has occurred and when probably all the free water has been removed from the system. For each of these stages there is a linear relation between time and log [c / (c – w) 1, where c is the total loss in weight on complete drying (approximately initial water content), and w is the loss in weight at time t. A drying constant has been calculated from this logarithmic function for the initial stage of drying, and has been used for determining the mechanism of drying. Water movements through the parenchymal cells are fast compared with those through the skin. Since various dipping treatments give different drying rates there is no rate-controlling diffusion through the stationary air layer a t the grape surface. The drying rate is controlled by the diffusion of water through the waxy cuticle, and is inversely proportional to the amount of cuticle present as determined by extraction with chloroform. The elastic contraction of the skin causes an increase in the thickness of the cuticle which reduces the permeability. The heat required for the evaporation of water and for heating the grape to the equilibrium drying temperature is transferred from the surroundings to the grape. The rate of drying increases rapidly with rise in temperature owing to the vapour pressure of water and the permeability of the cuticle increasing with the temperature.

scholarly journals Elaboração e aceitabilidade de macarrão tipo espaguete enriquecido com farinha de erva-sal (Atriplex nummularia L.)

2019 ◽  
Vol 1 (47) ◽  
pp. 104
Author(s):  
Thais Jaciane Araujo Rodrigues ◽  
Agdylannah Felix Vieira ◽  
Aline Chiara Dos Santos Trindade ◽  
Ana Paula Trindade Rocha ◽  
Deyzi Dos Santos Gouveia ◽  
...  
Keyword(s):  
Wheat Flour ◽  
Partial Substitution ◽  
Consumer Acceptability ◽  
Initial Water Content ◽  
Standard Formulation ◽  
Initial Water ◽  
Atriplex Nummularia ◽  
Forced Air ◽  
Air Circulation ◽  
Hygienic Conditions

<p>The objective of this experiment was to dry the leaves of salt grass (Atriplex nummularia) and to make pasta with partial substitution of wheat flour for salt-grass meal. The leaves, with an initial water content of 77%, were submitted to kiln drying with forced air circulation at 60 ° C. Spaghetti-type pasta was prepared in 0, 5, 10 and 15% wheat flour combinations and subjected to microbiological evaluation according to the current legislation, which resulted in satisfactory sanitary and hygienic conditions. The sensorial test was performed with 50 untrained judges, and we observed that the standard formulation, without the addition of the salt-grass meal had the highest scores in all the attributes evaluated while the formulation with 15% of saltgrass meal had the lowest scores. The study showed that percentages of less than 15% salt grass meal have good consumer acceptability. Regarding firmness, there has been an increase in it with the addition of salt-grass meal.</p>

Influence of initial water content and strain rate on remolded yield stress in marine clay

2021 ◽  
pp. 1-8
Author(s):  
Xiaobing Li ◽  
Jianpeng Chen ◽  
Xiuqing Hu ◽  
Hongtao Fu ◽  
Jun Wang ◽  
...  
Keyword(s):  
Strain Rate ◽  
Water Content ◽  
Yield Stress ◽  
Initial Water Content ◽  
Marine Clay ◽  
Initial Water

scholarly journals Application of the Calorimetric Methods to the Characteristics of Seeds from Olives

Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 90
Author(s):  
Andrzej Bryś ◽  
Joanna Bryś ◽  
Marko Obranović ◽  
Dubravka Škevin ◽  
Szymon Głowacki ◽  
...  
Keyword(s):  
Olive Oil ◽  
Water Content ◽  
Cooling System ◽  
Waste Product ◽  
Normal Pressure ◽  
Ash Content ◽  
Initial Water Content ◽  
Scanning Calorimetry ◽  
Initial Water

The olive oil industry represents an important productive sector in the Mediterranean basin countries. Olive stone is an essential by-product generated in the olive oil extraction industries and it represents roughly 10% by weight of the olive fruit. The seeds of pickled olives are also a significant waste product. In the present study, we have investigated the possibility of the use of differential scanning calorimetry for the thermal characterization of seeds from green and black pickled olives from Croatia. The differential scanning calorimeter (DSC) with a normal pressure cell equipped with a cooling system was used to determine the thermal properties of seeds from olives. The following analyses were also performed: the determination of calorific values in a pressure bomb calorimeter, the determination of initial water content, the determination of changes of water content during drying at the temperatures of 30 °C, 50 °C and 80 °C, the determination of a percentage content of seeds mass to the mass of the whole olives, and the determination of ash content. Seeds from olives are characterized by very good parameters as a biomass. The analyzed olive seeds were characterized by low water content, low ash content, and a relatively high caloric value.

scholarly journals RESEARCH ON MODEL FITTING AND STRENGTH CHARACTERISTICS OF CRITICAL STATE FOR EXPANSIVE SOIL

2013 ◽  
Vol 19 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Zhiqing Li ◽  
Chuan Tang ◽  
Ruilin Hu ◽  
Yingxin Zhou
Keyword(s):  
Critical State ◽  
Model Fitting ◽  
Expansive Soil ◽  
Dry Density ◽  
Initial Water Content ◽  
Test Results ◽  
Stress Strain ◽  
Initial Water ◽  
Curve Model ◽  
Shearing Strength

According to Mengzi expansive soil, consolidated drained tests and undrained tests are carried on under saturated and remoulded conditions. The stress-strain characteristics of saturated soil are researched systematically under different confining pressure, initial dry density, initial water content, shearing rate and drainage condition. The inherent unity of diversity of shearing strength for the same samples measured by different experimental methods is indicated according to the normalization of critical state test results. And the failure lines in p ‘- q - ν space of remoulded saturated expansive soil under consolidated drained and undrained conditions are attained. The hyperbolic curve model can fit well the weak hardening stress-strain curves and the exponential curve model can fit the weak softening stress-strain curves. The test results can provide technical parameters and theoretical help for shearing strength variation of slope during rainfall and strength state of soil structure in normal water level.

THREE-DIMENSIONAL SEEPAGE ANALYSIS OF A COAL REFUSE PILE RECLAMATION

2020 ◽  
Vol 9 (4) ◽  
pp. 44-66
Author(s):  
Iuri Lira Santos ◽  
Keyword(s):  
Mine Drainage ◽  
Characteristic Curve ◽  
Water Volume ◽  
Low Permeability ◽  
Initial Water Content ◽  
Initial Water ◽  
Seepage Analysis ◽  
Cover System ◽  
Coal Refuse ◽  
Refuse Pile

Abstract. A coal refuse pile located in Greenbrier County, West Virginia was studied to restrict generation of acid mine drainage through the use of a cap and cover system. This paper presents results of a finite element method seepage analysis on a proposed reclamation design. The proposed reclamation incorporates a cap and cover system with a 0.3-m thick surface vegetation cap layer over a 0.6-m thick low permeability layer. The low permeability layer is directly above the coal refuse. Unsaturated soil mechanics was utilized, adopting the Fredlund and Xing equation for soil-water characteristic curve (SWCC) estimation. SWCC fitting parameters were calculated using the Zapata and the Hernandez estimation techniques. Different precipitation events were used to evaluate seepage throughout the reclamation area and assess the effectiveness of the cap and cover system. A steep area (>4H:1V) and a flat area were considered. The water balance analysis showed a 50% to 88% reduction in water volume at the coal refuse layer and a reduction in the time for the refuse to return to initial water content due to the cap and cover system implementation. Moisture detainment was observed in the growth layer and is important for supporting vegetation persistence.

scholarly journals Effects of Initial Water Content on Microstructure and Mechanical Properties of Lean Clay Soil Stabilized by Compound Calcium-Based Stabilizer

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1933 ◽  
Author(s):  
Chenglong Yin ◽  
Wei Zhang ◽  
Xunli Jiang ◽  
Zhiyi Huang
Keyword(s):  
Water Content ◽  
Soil Stabilization ◽  
Clay Soil ◽  
Soil Aggregates ◽  
Optical Microscope ◽  
Initial Water Content ◽  
Reaction Products ◽  
Unconfined Compression Test ◽  
Initial Water ◽  
X Ray

Initial water content significantly affects the efficiency of soil stabilization. In this study, the effects of initial water content on the compressibility, strength, microstructure, and composition of a lean clay soil stabilized by compound calcium-based stabilizer were investigated by static compaction test, unconfined compression test, optical microscope observations, environment scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. The results indicate that as the initial water content increases in the range studied, both the compaction energy and the maximum compaction force decrease linearly and there are less soil aggregates or agglomerations, and a smaller proportion of large pores in the compacted mixture structure. In addition, for specimens cured with or without external water supply and under different compaction degrees, the variation law of the unconfined compressive strength with initial water content is different and the highest strength value is obtained at various initial water contents. With the increase of initial water content, the percentage of the oxygen element tends to increase in the reaction products of the calcium-based stabilizer, whereas the primary mineral composition of the soil-stabilizer mixture did not change notably.

scholarly journals Solidification of High Organic Matter Content Sludge by Cement, Lime and Metakaolin

2018 ◽  
Author(s):  
Ke Rui ◽  
Wang Hongxing ◽  
Tan Yunzhi ◽  
Wang Lehua
Keyword(s):  
Organic Matter ◽  
Water Content ◽  
Organic Matter Content ◽  
Microscopic Analysis ◽  
Chemical Components ◽  
Orthogonal Experimental Design ◽  
Initial Water Content ◽  
Initial Water ◽  
Lime Content ◽  
Sheet Structure

Based on orthogonal experimental design, the key solidification controlling technology of Solidified/Stabilized (S/S) sludge with high total organic content (TOC) by cement, lime and metakaolin was explored by macroscopic tests, chemical components measurements and microscopic analysis. The macroscopic tests show that, the permeability coefficient is mainly affected by initial water content and lime content, and the unconfined compression strength is mainly affected by cement content and lime content. The chemical components measurements show that, the solidification effect of S/S sludge with high TOC is controlled by organic matter consumption, and organic matter consumption is determined by the alkaline environment from the cement and lime hydration reactions, which is mainly affect by the initial water content and lime-metakaolin content ratio. The microscopic analysis results show that, lime consumes parts of organic matter while excess lime produces weak Ca(OH)2 crystal fluffy sheet structure, matakaolin produces pozzolanic reactions with cement and lime instead of soil particles, and consumes the weak Ca(OH)2 crystal fluffy sheet structure produced by superfluous lime. The research has confirmed key controlling points of S/S sludge in case of high TOC, which will provide theoretical guidance and technical support for S/S sludge promotion with high TOC.

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