scholarly journals Numerical Modelling of Moisture Loss during Controlled Drying of Marine Archaeological Wood

Forests ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1662
Author(s):  
Gabriel Lipkowitz ◽  
Karoline Sofie Hennum ◽  
Eleonora Piva ◽  
Eleanor Schofield
Keyword(s):  
Moisture Content ◽  
Numerical Modelling ◽  
Visual Observation ◽  
Moisture Loss ◽  
Conservation Strategies ◽  
Residual Water ◽  
Archaeological Wood ◽  
Sample Depth ◽  
Representative Model ◽  
First Time

If left to dry uncontrollably following excavation, marine archaeological wood suffers significant and irreparable damage. Conservation treatments are required to consolidate degraded wood and to remove residual water. Drying must be controlled to eliminate erratic and heterogeneous water removal. Monitoring and understanding the drying process progression is invaluable information to garner real-time knowledge to correlate with chemical and physical material properties, and to develop future conservation strategies. Here, polyethylene glycol (PEG) consolidated marine archaeological wood was periodically sampled during drying to determine the moisture content as a function of location, time, and sample depth. The heterogeneous nature of the material leads to significant noise across spatial and temporal measurements, making it challenging to elucidate meaningful conclusions from visual observation of the raw data. Therefore, the spatiotemporal data was computationally analysed to produce a representative model of the ship’s drying, illustrated by a dynamic simulation. From this we can quantitatively predict the drying rate, determine the depth-dependence of drying, and estimate the resulting equilibrium moisture content. This is the first time such simulations have been carried out on this material and conservation process, demonstrating the power of applying numerical modelling to further our understanding of complex heritage data.

The Smoulder Stream of Cigarettes / Zur Kenntnis des Glimmstromes von Cigaretten

1965 ◽  
Vol 3 (2) ◽  
Author(s):  
F. Seehofer ◽  
W. Schulz
Keyword(s):  
Moisture Content ◽  
Spatial Position ◽  
High Yield ◽  
Physical Conditions ◽  
Moisture Contents ◽  
Cigarette Paper ◽  
First Time

AbstractThe phenomenon of the smoulder stream flowing through the cigarette during smouldering and during the puff intervals is demonstrated for the first time and its dependence upon physical conditions is examined. The volume of the smoulder stream can amount up to 180 ml per cigarette. Increasing draw resistance of the cigarette and augmenting moisture content of the tobacco as well as perforation of the cigarette paper have a decreasing effect on volume and velocity of the smoulder stream. The porosity of the cigarette paper has no perceptible influence. The spatial position of the cigarette affects volume and velocity of the smoulder stream. The influence exercised by the smoulder stream on the yields of total condensate, nicotine, phenols, aldehydes, and acroleine when the cigarette tip is open during the puff intervals is determined. When the moisture contents of the tobacco were extremely high, yield decreases reaching 50 % could be observed.

Determination of readiness for laying based on material moisture, corresponding relative humidity, and water release

2020 ◽  
Vol 62 (10) ◽  
pp. 1033-1040
Author(s):  
Christoph Strangfeld ◽  
Sabine Kruschwitz
Keyword(s):  
Relative Humidity ◽  
Moisture Content ◽  
Embedded Sensors ◽  
Residual Water ◽  
Floor Covering ◽  
Water Release ◽  
Content Determination ◽  
Two Samples ◽  
Moisture Content Determination

Abstract The moisture content of the subfloor has to be determined before installation to avoid damage to the floor covering. Only if readiness for layering is reached, can an installation without damage be expected in all cases. In general, three approaches exist to measure residual water content: determination of moisture content, determination of water release, or determination of the corresponding relative humidity. All three approaches are tested under laboratory conditions at eight screed types including two samples thicknesses in each case. Moisture content and water release are measured by sample weighing, the corresponding relative humidity is measured by embedded sensors. All three approaches are compared and correlated. The evaluations show only a weak correlation and, in several cases, contradicting results. Samples are considered ready for layering and not ready for layering at the same time, depending on the chosen approach. Due to these contradicting results, a general threshold for a risk of damage cannot be derived based on these measurements. Furthermore, the experiment demonstrates that the measurement of corresponding relative humidity is independent of the screed type or screed composition considered. This makes humidity measurement a potentially very promising approach for the installation of material moisture monitoring systems.

Biodiversity in the Andean Mountains: Two new rain frogs of the genus Pristimantis (Anura: Craugastoridae) from the northern Cordillera Central in Colombia

Zootaxa ◽  
2021 ◽  
Vol 5040 (3) ◽  
pp. 334-364
Author(s):  
MAURICIO RIVERA-CORREA ◽  
GUSTAVO A. GONZÁLEZ-DURÁN ◽  
ANA M. SALDARRIAGA-GÓMEZ ◽  
SEBASTIÁN DUARTE-MARÍN
Keyword(s):  
New Species ◽  
Species Delimitation ◽  
Intraspecific Diversity ◽  
Conservation Strategies ◽  
Phylogenetic Position ◽  
The Andes ◽  
Two New Species ◽  
Diversity Studies ◽  
First Time ◽  
Central Cordillera

Frequent biodiversity sampling and monitoring programs often lead to relevant taxonomic findings. Here, as a product of different field expeditions to two places in the northern Andes, we discover and describe two new species of rain frogs of the genus Pristimantis from the cloud forests of the Central Cordillera of Colombia. Pristimantis chocolatebari sp. nov. is diagnosed by having the following character states: dentigerous process of vomer triangular, snout large and protruding, dorsum smooth, vocal slits and vocal sac present, groin and hidden part of the thighs yellow. Pristimantis carylae sp. nov. is diagnosed by having iris copper red, dentigerous process of vomer oval, snout short and rounded, dorsum finely shagreen with scattered tubercles, double nuptial pad in males, groin and hidden part of thighs pink. We also infer, for the first time, the phylogenetic position of P. permixtus, P. platychilus, and two candidate new species. In addition, we emphasize not to use genetic distance as the only source of evidence for species delimitation, considering the high intraspecific diversity found in one of the species described here. Finally, we highlight the relevance of different habitat and ecosystem conservation strategies to promote amphibian diversity studies in the Andes.  

scholarly journals Effect of Drying on the Rehydration Properties of Some Selected Shellfish

2020 ◽  
pp. 42-48
Author(s):  
D. B. Kiin-Kabari ◽  
N. Obasi
Keyword(s):  
Moisture Content ◽  
Proximate Composition ◽  
Crude Protein ◽  
Moisture Loss ◽  
Rehydration Ratio ◽  
Crude Fibre ◽  
Oven Drying ◽  
Water Imbibition ◽  
Nutritional Qualities ◽  
Sample Water

This study was conducted to evaluate the effect of oven drying on the proximate composition and rehydration characteristics of shellfish. Shellfish studied included rough and smooth periwinkle, oyster and whelk. Proximate composition of the fresh samples were determined. Then dried in the oven to a moisture content of 10% and further rehydrated with distill water in sample water ratio of 1:40 and allowed to equilibrate. Proximate composition of the fresh shellfish showed that moisture content ranged from 82.38 to 69.24% with fresh smooth periwinkle having the highest moisture value while whelk had the lowest. The results also showed that whelk had the highest values for ash (2.92%), crude protein (18.83%) and crude fibre (3.71%) when compared to other samples. On rehydration, a moisture loss of 11.75%, 13.28%, 19.24% and 22.04% were observed for rough periwinkle, smooth periwinkle, oyster and whelk, respectively. The results for rehydration indices revealed that dehydration ratio was significantly (p<0.05) high for whelk (1.44), followed by oyster (1.29), rough periwinkle (1.23) and lastly, smooth periwinkle 1.20. Rehydration ratio of whelk (1.47) was equally significantly higher, followed by oyster (1.33) and the least were rough and smooth periwinkle (1.17). For coefficient of reconstitution, oyster recorded the highest value of 1.03, followed by whelk 1.02, rough periwinkle 0.95 and smooth periwinkle 0.98. Rate of water imbibition revealed a sharp increase in the water content of smooth periwinkle up to 240 min and thereafter, it slowed down until equilibrium was reached. In terms of rough periwinkle, oyster and whelk; water imbibition took place with rehydration time up to 300 min, 210 min and 270 min, respectively, thereafter they slowed down. The results have demonstrated that the rate in which oven drying affect the physical and nutritional qualities of shellfish differs.

scholarly journals A Study on Factors Influencing the Determination of Moisture Content of Fibrous Peat

2011 ◽  
Vol 2 (2) ◽  
pp. 39-47 ◽  
Author(s):  
Pui Tau Shien ◽  
Seneviratne H.N. ◽  
Dygku Salma Awg Ismail
Keyword(s):  
Moisture Content ◽  
Particle Density ◽  
Peat Soil ◽  
Test Procedure ◽  
Field Measurements ◽  
Standard Test ◽  
Moisture Loss ◽  
Fibrous Peat ◽  
Saturated Sample

Fibrous peat is an undrained peat that usually possesses very high moisture content. However, not all experimental procedures are applicable for determination of moisture content of fibrous peat. This research is aimed at examining the determination of insitu moisture content of fibrous peat using field measurements. The peat soil samples were collected at shallow depths from Asajaya at Kota Samarahan and Taman Kopodims at Matang , Kuching Sarawak by using peat auger. The laboratory tests such as determination of moisture content, fiber content, particle density and ash content were conducted on the collected samples in order to establish relationships between the parameters. Undisturbed peat samples from Matang were subjected to falling head permeability test to determine the saturated permeability. The saturated sample were then allowed to drain freely to simulate the moisture loss possible during sampling when samples were brought out of boreholes. The test results showed that moisture content varies according to the drying temperature and position of the soil sample (top, middle and bottom) during sampling. Comparing samples from both locations, peat soil from Kota Samarahan possessed higher moisture content. The saturated permeability of peat sample was in the range of 2.62 – 3.05 cm/s. The free draining trial showed that moisture loss during sampling significantly influence the moisture content measurement. The variation in value of moisture content for fibrous peat may occurs due to several factors such as existing ground water table, sampling method by boring, existing standard test procedure which is not suitable for peat soils requirement and also because of the physical properties which varied according to depth of soil.

scholarly journals MOISTURE CHANGES IN LODGEPOLE PINE BEFORE AND AFTER ATTACK BY THE MOUNTAIN PINE BEETLE

1961 ◽  
Vol 37 (4) ◽  
pp. 368-375 ◽  
Author(s):  
R. W. Reid
Keyword(s):  
Moisture Content ◽  
Mountain Pine Beetle ◽  
Lodgepole Pine ◽  
Dry Weight ◽  
Moisture Loss ◽  
Mountain Pine ◽  
Pine Beetle ◽  
Before And After ◽  
Blue Stain ◽  
One Year

The moisture content of the outer sapwood of non-infested lodgepole pine is normally about 85 to 165 per cent of oven dry weight. In trees that have been infested by the mountain pine beetle for one year, the sapwood moisture content can be as low as 16 per cent. There is a steep moisture gradient from about 160 per cent in the outer sapwood to about 30 per cent in the heart-wood. The moisture content in the centre is slightly higher than in the adjacent wood. In infested trees the sapwood moisture is greatly reduced within a year after the attack but moisture in the heartwood is not altered appreciably. Trees infested early in the season drop to a lower moisture content by fall than trees infested later in the season. In non-infested trees there is a diurnal and a seasonal moisture march; these do not occur in infested trees. The rapid moisture loss in the sapwood of infested trees is associated with blue-stain infection and successful establishment of bark-beetle broods

Study on the Enzyme Activity Change during the Aerobic Composting Process of Sewage Sludge

2014 ◽  
Vol 955-959 ◽  
pp. 706-710
Author(s):  
Jun Ling Niu ◽  
Jun Hui He
Keyword(s):  
Enzyme Activity ◽  
High Temperature ◽  
Sewage Sludge ◽  
Moisture Content ◽  
Cellulase Activity ◽  
Moisture Loss ◽  
Intensity Change ◽  
Composting Process ◽  
Activity Intensity ◽  
Sludge Disposal

Compost is widely used for treating urban garbage and sewage sludge. The enzyme activity is one of the important parameters of microbial quantity and its activity intensity change in the composting process, and all of the biochemical reactions during the composting process are carried out with the enzymes involving. The composting progress and the material change are directly reflected by the enzyme activity. In Zhengzhou Bagang sludge disposal plant, sludge was mixed with straw to compost together and with the technology of high temperature solid state aerobic slot for sludge treatment. This study was done to research the tendency of peroxide enzyme activity, cellulose enzyme activity, pH, conductivity, moisture content in the process of compost. The result showed that at the beginning of the compost, cellulase activity increased first and then decreased gradually and tended to be stable. The catalase activity was higher at the beginning of the compost and at the period of temperature raising it was stable basically, then decreases quickly and after that it maintain on the lower level. The moisture content declined gradually during the composting process, and in the period of high temperature there are more moisture loss. PH increased at first, and with the temperature raised to high the pH decreased gradually and tended to be stable. Conductivity increased first, then decreased gradually to steady.

Drying technology of mesquite pods (Prosopis laevigata) and microstructural insights

2020 ◽  
Vol 122 (9) ◽  
pp. 2953-2963
Author(s):  
Sadoth Sandoval Torres ◽  
Daniel Lopez Cravioto ◽  
Juan Rodríguez Ramírez ◽  
Lilia L. Méndez Lagunas ◽  
Luis Gerardo Barriada Bernal ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Moisture Content ◽  
Food Industry ◽  
Characteristic Curve ◽  
Drying Process ◽  
Sem Images ◽  
Content Type ◽  
Milling Operation ◽  
Drying Technology ◽  
First Time

PurposeMesquite pods offer a high nutritional content; A flour can be produced from them; nevertheless, the moisture content makes the milling process difficult. Then, before the milling operation a drying process must be implemented, but drying technology must be studied in order to characterise the process and identify the effect of drying temperature on the magnitude of drying rate.Design/methodology/approachProsopis Laevigata pods were collected in Oaxaca (Southern of Mexico) and they were dried. Three stages of maturity were identified and pods in the stage three of maturity were dried by forced convection. The internal structure of the pods was analyzed by scanning electron microscopy (SEM). The pods were dried in a tunnel dryer at 40, 50, 60 and 70° C, 10% relative humidity and air velocity of 2.6 m/s. From experimental data, a lumped analysis was conducted for drying.FindingsWe found that the internal microstructure of this material is a limiting factor for moisture migration. In order to reduce the moisture content in the pods, a minimum air temperature of 60° C must be applied. The characteristic drying curve shows a good agreement with the experimental drying kinetics. The nutritional composition (carbohydrates, sugar and protein) of pods reveals important applications for the food industry.Practical implicationsThe mesquite pods are important ethnic foods. In order to obtain flour, the drying of pods is mandatory. Drying must be applied in stage three of maturity which can be identified based on color changes and moisture content. The moisture content affects the performance of milling operation, then a minimum drying temperature of 60° C and low relative humidity must be applied. SEM images show the complex microstructure of the pods which hinders the moisture diffusion. The drying characteristic curve was deduced for the first time; it helps to understand the drying behavior of pods. The chemical composition of mesquite pods reveals interesting applications for the food industry. The methodology for drying is useful for researchers and producers.Originality/valueMezquite pods is an interesting ethnic food for people with celiac disease. This is the first time a research paper describes the drying process at detail. The SEM images, the convective drying operation and the characteristic curve are presented for the first time. The information will be useful for the industry and academia.

HYSTERESIS EFFECTS IN SOIL MOISTURE MOVEMENT

1962 ◽  
Vol 42 (2) ◽  
pp. 247-253 ◽  
Author(s):  
W. J. Staple
Keyword(s):  
Moisture Content ◽  
Past History ◽  
Rate Of Change ◽  
Moisture Loss ◽  
Time Intervals ◽  
Moisture Movement ◽  
Wetting And Drying ◽  
The Past ◽  
History Of ◽  
Different Depths

Hysteresis was assessed by measuring the tension and moisture content of sections of soil at different time intervals during the redistribution of moisture in uniformly packed columns of Grenville silt loam. Moisture tension was measured by a null method and moisture content was measured gravimetrically.The rate of change of tension with moisture content dψ/dθ and hence the diffusivity, in the tension range 25 to 400 centimeters of water was more than twice as great for drying as for wetting. During redistribution of moisture, when both drying and wetting were involved, different ψ, vs. θ relationships existed at different depths, and the slopes dψ/dθ and diffusivities in the profile were often lower than those for either drying or wetting alone.Further work is needed to assess the importance of hysteresis on moisture movement in practical problems. It seems possible that data on hysteresis, and a knowledge of the past history of wetting and drying, may provide estimates of moisture loss and conservation in fallowed fields.

scholarly journals Ethnomedical Knowledge of Plants Used for the Treatment of Tuberculosis in Johor, Malaysia

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Siti Fatimah Sabran ◽  
Maryati Mohamed ◽  
Mohd Fadzelly Abu Bakar
Keyword(s):  
Medicinal Plants ◽  
Sampling Technique ◽  
Conservation Strategies ◽  
Herbarium Specimens ◽  
Transfer Of Knowledge ◽  
Snowball Sampling ◽  
Semistructured Interviews ◽  
Biomedical Terminology ◽  
Emic Perspective ◽  
First Time

This study documented ethnomedical knowledge of plants used for the treatment of tuberculosis (TB) and its related symptoms as practiced by the Jakun community of Kampung Peta, situated in Endau Rompin Johor National Park, Johor, Malaysia. Eight key informants were selected by snowball sampling technique and data about medicinal plants were collected by semistructured interviews, participatory observations, and focus group. Qualitative analysis was undertaken using thematic analysis. There were 23 species of plants (22 genera, 20 families) documented and herbarium specimens were deposited at the UTHM Herbarium.Dipterocarpus sublamellatuswas recorded for the first time with ethnomedical uses while other species were previously reported. The qualitative approach employed in this study demonstrates the emic perspective in terms of perceptions on traditional herbal medicine, transfer of knowledge, significant taboos related with medicinal plants, and their conservation efforts. Local and biomedical terminology in treatment of TB showed substantial correspondence. The outcomes obtained in the study are worth being further investigated for conservation strategies and are worthy of verifying their ethnomedical claims scientifically.

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