Changes In Moisture Content Research Articles

LOW-COST DEPTH-CAMERA: OPEN-SOURCE 3D DISPLACEMENT MEASUREMENTS FOR 4D PRINTED HYGROSCOPIC COMPOSITES

Abstract. 4D printing (4DP) is a growing branch of 3D printing technology that involves the design of composite material architectures capable of shape-change transformations, which occur post printing, in response to external stimulus. Among these, Wood Polymer Composites (WPCs) change their shape in reaction to changes of moisture content, shrinking or swelling like natural wood until the equilibrium with the environment is reached. Such intrinsic material behavior can be particularly useful in the development of passive moisture airflow controllers that can modulate humidity and airflow in indoor environments to improve air quality. Precise measurement of the time-based stimulus induced shape-change response of these composites is critical to assess the responsiveness, velocity of reaction and overall deformation of the designed 4DP composite mechanisms. Up until now, Digital Image Correlation (DIC) techniques have been widely used for such purpose. However, DIC methods require expensive equipment and costly commercial software. This paper presents a Low-Cost Depth-Camera (LCDC) method that uses a free custom algorithm that returns a 3D coloured displacement map with the corresponding meshes of the acquired object. The LCDC method does not require specialized equipment and allows for an overall understanding of the time-dependent deformation of 4DP actuators, this method also facilitates the comparison between composites with different properties under the same external conditions. This new LCDC method has the potential to further 4DP research by providing an open-source, accessible and reliable tool to assess 3D displacement measurements.

Sistema IoT para el cuidado de plantas ornamentales

The Internet of Things (IoT) has allowed to connect heterogeneous devices to offer new services and applications to users using information of the environment. The goal of this paper is to present an IoT-System to continuously monitor changes in the soil moisture content and ambient temperature of ornamental plants. In addition, an irrigation system was implemented to maintain the soil moisture of the plants within a time interval. The activation time of the water pump constitutes the estimated variable of the proposed automated IoT -System, so the research methodology was applied in carrying out tests and experimentations related to this variable. The irrigation system can be activated from an App developed in Android, likewise, a proposed electronic system based on Arduino and the ESP8266-201 microchip has been developed, and the communication between the ESP8266 and Arduino is achieved through AT commands. As a complement, SigFox technology has been proposed to collect and store the plant's soil moisture measurement values in a database server. The proposal presents important results to determine intervals of time and amount of water to supply for ornamental plants.

Regular Changes in Soil Moisture Content in Coniferous Forests of the Udyly State Nature Reserve, Lower Amur River Region

Regular Changes in Soil Moisture Content in Coniferous Forests of the Udyly State Nature Reserve, Lower Amur River Region

Calculation of change of stock moisture content of the drying agent in the process of drying raw cotton in solar drying equipment

The article covers one of the urgent tasks, i.e. energy-saving, analytical calculation of the stock moisture content of the drying agent in the process of drying raw cotton in solar dryer with optical magnifiers, considering the various climatic conditions of Uzbekistan, has been developed, a method for calculating the change in the absolute and relative humidity of the drying agent when drying raw cotton using mathematical models has been developed.

Evolution of Composition and Methane Occurrence of Bituminous Coal after Igneous Intrusion: A Case Study of Daxing Coal Mine, Tiefa Basin, China.

Since 1987, there have been 10 coal and gas outbursts in Daxing Coal Mine, Tiefa Basin. It was reported that these outbursts were related to igneous intrusion. To study the influence of igneous intrusion into bituminous on coal bed methane (CBM) occurrence, eight coal samples were collected at different distances (0.2-10 m) from an intrusion in Daxing Coal Mine. The petrographic and chemical data, pore characteristics, and adsorption properties of unaltered and heat-affected coals were tested and compared. Approaching the dike, vitrinite reflectance (R o) increases from 0.56 to 1.14%, while moisture decreases from 6.4 to 3.1%. According to R o, with the thermal evolution of igneous rocks, the temperature of heat-affected coal seams generally increases from ∼78 to ∼169 °C. The bituminous coal contained high moisture content before the intrusion, and after the igneous intrusion, partial heat may be used for moisture gasification; the other heat was used to improve coal metamorphism, resulting in little increase in the coal metamorphism as expected. The synergistic effect of igneous thermal evolution and moisture content change improves the adsorption capacity of coal. Affected by the igneous intrusion, the gas content of the heat-affected coal seams No. 4 (above the sill) and No. 7 (below the sill) is higher than that of the unaltered No. 12 coal seam, and the gas content of No. 7 coal seam (beneath the sill) is higher than that of No. 4 coal seam. The low permeability sill has a sealing effect on the gas in No. 7 coal seam. Therefore, the evolution process of CBM occurrence in the Daxing Coal Mine can be speculated, that is, after magma intrusion, the temperature increased, the metamorphic degree of coal increased, and water gasification occurred at the same time. The original adsorption site occupied by moisture was vacated, which improved the methane adsorption capacity of the coal and provided favorable conditions for CBM occurrence.

Pressure development and volume changes during frying and post-frying of potatoes

Pressure evolution and material deformation during frying and post-frying of foods affect transport processes and food's textural attributes. Pressure and volume measurements have received limited attention in the frying literature. In this study, the changes in moisture content, oil uptake, temperature, pressure, and volume were measured as a function of frying time for potato cylinders. The volume change immediately after frying and after the cylinders had cooled was measured using a modified liquid displacement method. Fried cylinders continued to shrink post-frying. During frying, pressure and temperature showed similar increasing trends followed by plateauing of the temperature and a drop in pressure in the core. The measured gauge pressure remained positive throughout frying (t=300s) and up to 100s after frying. The measured gauge pressure dropped to negative values for the remaining cooling period. The temperature decreased during cooling, which is expected to have led to water vapor collapse and a drop in gas pressure. A high capillary pressure is expected to have developed in the food matrix due to water loss, causing the effective gauge pressure to become negative. The negative gauge pressure is expected to drive oil uptake and shrinkage of the food matrix post-frying.

Parameters of Agricultural Product Dryer

The problem of drying quality in existing installations is considered. It is proposed to carry out the analysis of heat and moisture transfer in the Comsol complex. As a result of modeling, dependences of changes in temperature and moisture content of raw materials on time were obtained. A rational geometry of the location of the dryer trays and the addition of convective heating with an IR emitter are recommended, which contributes to the formation of a more uniform moisture content of the dried product and a reduction in the process time.

Reliability of using vegetation optical depth for estimating decadal and interannual carbon dynamics

Vegetation optical depth (VOD) from satellite passive microwave sensors has enabled monitoring of aboveground biomass carbon dynamics by building a relationship with static carbon maps over space and then applying this relationship to VOD time series. However, uncertainty in this relationship arises from changes in water stress, as VOD is mainly determined by vegetation water content, which varies at diurnal to interannual scales, and depends on changes in both biomass and relative moisture content. Here, we studied the reliability of using VOD from various microwave frequencies and temporal aggregation methods for estimating decadal biomass carbon dynamics at the global scale. We used the VOD diurnal variations to represent the magnitude of vegetation water content buffering caused by climatic variations for a constant amount of dry biomass carbon. This magnitude of VOD diurnal variations was then used to evaluate the likelihood of VOD decadal variations in reflecting decadal dry biomass carbon changes. We found that SMOS-IC L-VOD and LPDR X-VOD can be reliably used to estimate decadal carbon dynamics for 76.7% and 69.9% of the global vegetated land surface, respectively, yet cautious use is warranted for some areas such as the eastern Amazon rainforest. Moreover, the annual VOD aggregated from the 95% percentile of the nighttime VOD retrievals was proved to be the most suitable parameter for estimating decadal biomass carbon dynamics among the temporal aggregation methods. Finally, we validated the use of annual VOD for estimating interannual carbon dynamics by comparing VOD changes between adjacent years against eddy covariance estimations of gross primary production from flux sites over several land cover classes across the globe. Despite the large difference in spatial scales between them, the positive correlation obtained supports the capability of satellite VOD in quantifying interannual carbon dynamics.

Stabilization Expansive Clayey with Nano-Lime to Reduce Environmental Impact

For years, geotechnical engineers have been concerned about expansive soils. Expansive soils are characterized by large volumetric changes related to variations in moisture content. Variations in soil water content may take place naturally during seasonal changes or maybe manmade caused by dewatering activities. The quantity of shrinkage and swell is influenced by numerous parameters, including the quantity of minerals clay in the soil, moisture content, dry density, and climate change. In most countries, numerous structures, including pavements and buildings, are damaged as a result of this shrinkage/swelling. Several ground improvement techniques are available for stabilizing expansive soil to modify its engineering performance. These methods include soil replacement, mixing with chemical additives, and soil reinforcement. The present study expressions the effect of nano-lime (i.e., 0.1, 0.3, 0.5, 0.7, 1.0, 2.0 and 3.0%), and lime (1, 3, 5, 8, and 10%), as chemical additive to improve clayey soil (i.e., illite and kaolinite). The effect of nano-lime and lime were investigated using Atterberg’s limits tests. The Atterberg limits were screening significant changes in the proportion of additional nano-lime and lime. The results show that less amount of nano-lime (1% and 2% for illite and kaolinite respectively) decreased the plastic limit, while for lime it was reported 8% for illite and 5% for kaolinite respectively. In conclusion, less quantity of nano-lime (1-2%) is able to improve soil parameters.

Dynamic changes in soil moisture in three typical landscapes of the Heihe River Basin

The water diversion scheme of Heihe River Basin was implemented in 2000. Herein, we investigated the dynamic changes in soil moisture content and analyzed the fundamental reasons supporting the water diversion plan in this typical inland river basin in northwest China. Accordingly, we selected three typical landscape gradients—a mountain water conservation forest belt, an artificial sand-fixing forest belt at the edge of a desert oasis, and a desert riparian forest belt in the upper, middle, and lower reaches of the Heihe River Basin, respectively. In these diverse landscapes, an environmental measuring system was used to continuously monitor the dynamic and differentiation regularity of soil moisture in the 0–160 cm layer for 5 years. The results revealed that 1) the soil moisture content in each landscape increased and varied significantly across seasons. In the upper and middle reaches, the soil moisture content was significantly higher during the growing season than in the non-growing season, whereas the lower reach displayed a converse pattern. 2) The distribution of soil moisture at various depths of soil profiles varied significantly for each landscape. As the soil depth increased, the soil moisture in the upper reach decreased. Although the deep layers (120–160 cm) could store water in the non-growing season, the stored water was consumed during the growing season. The soil moisture content in the mid-reach initially increased, later decreased, and ultimately attained its highest level at 40–60 cm; however, the soil moisture content in the lower reach increased, and reached its highest level at 120–160 cm. 3) In the upper and middle reaches, the coefficient of variation of soil moisture decreased with an increasing soil depth, whereas the lower reach exhibited a converse trend. Similarly, the coefficient of variation of soil water storage were higher during the non-growing season than during the growing season within the upper and middle reaches, whereas an opposite trend was observed in the lower reach. 4) Since the implementation of the Heihe river water diversion plan, the soil moisture content in both the upper and middle reaches have increased but that of the lower reach has fluctuated and declined, especially in the shallow depths during the growing season. The present findings imply that the lower reaches of the Heihe River may require additional water transfers during the growing season.

Correlation of ground penetrating radar and 2-D resistivity imaging methods towards shallow subsurface layer at coastal area

There is potential for a long-term subsidence trend on reclaimed land from the shoreline that may cause a geohazard in the future. This study conducted ground penetrating radar (GPR) and the 2-D resistivity method within the residential area in Teluk Kumbar, Pulau Pinang. This residential area is built on reclaimed land about 100 m from the shoreline. The purpose of this study is to identify subsidence in the coastal environment by considering the impact of seasonal variations using both surveys. The influence of wet and dry seasons on GPR and resistivity for the subsurface condition can be determined precisely after evaluating the attenuation of electromagnetic and resistivity values. The resistivity results show three lithology classes: reclaimed soil (>600 Ωm), original soil (<400 Ωm) and hard material (>1000 Ωm) during the dry season. Meanwhile, GPR signals support resistivity results with clear interfaces between reclaimed-original soil and original soil-hard material. GPR signals on layer interfaces have significantly reduced during the wet season due to the increased conductivity. The resistivity results also show decreases as the conductivity increases. Besides, a thick saturated zone of original soil formation has expanded in size during this season with a low resistivity value (<100 Ωm) and weak amplitude reflection. This zone tends to undergo shrink and swell processes due to moisture content changes, which can also correspond to subsidence. Overall, this study provides a good correlation between the performance of geophysical techniques and seasonal changes that accurately characterize the subsurface layer.

Research of Deformation and Soil Moisture in Loess Landslide Simultaneous Retrieved with Ground-Based GNSS

The Loess Plateau is one of the three most severely affected geological disaster areas in China. Water sensitivity is the most significant feature of the loess. Under the action of continuous heavy rainfall, rainwater infiltrates the loess, resulting in a rapid increase in soil saturation and changes in soil moisture. This affects the shear strength of the soil and induces shallow loess landslides. Therefore, it is significant to our country’s disaster prevention and mitigation efforts to effectively monitor the deformation and inducement of such landslides. At present, the global navigation satellite system (GNSS) is widely used in the field of landslide disaster monitoring as a technical means to directly obtain real-time three-dimensional vector deformation of the surface. At the same time, GNSS can also provide a steady stream of L-band microwave signals to obtain surface environmental information, such as soil moisture around the station. In past landslide disaster monitoring research, GNSS was only used to provide three-dimensional deformation information, and its ability to provide environmental information around the station was almost completely ignored. This study proposes a ground-based GNSS remote sensing comprehensive monitoring system integrating “three-dimensional deformation and soil moisture content” combined with a rainfall-type shallow loess landslide event in Linxia City. The ability of ground-based GNSS to comprehensively monitor shallow loess landslide disasters was analysed. Experiments show that GNSS can provide high-precision deformation time series characteristics and monitor the changes in soil moisture content around the station at the same time; the two have a certain response relationship, which can comprehensively evaluate the stability of shallow loess landslides. As heavy rainfall is a key factor affecting the change in soil water content, this study adds the atmospheric water vapour content calculated by ground-based GNSS refraction remote sensing in the discussion chapter and analyses the relationship between precipitable water vapour and rainfall in this area to give full play to ground-based GNSS remote sensing. In the role of landslide disaster monitoring, we hope to build a more comprehensive ground-based GNSS remote sensing monitoring system to better serve the monitoring of landslide disasters.

Discrete Heaped Model of Tobacco Strips Drying and Characteristics Analysis of Heat and Mass Transfer

To accurately study the drying characteristics of tobacco strips in the process of redrying, a discrete heaped physical model of tobacco strips is built. Based on this model, a convective drying multiphase porous media model of the heaped tobacco strips is established, which considers the binary diffusion and transport of vapor inside and outside the tobacco leaf. The model is solved using COMSOL Multiphysics, and the accuracy of the model is verified by experiments. The changes in hot air velocity, vapor and moisture content, and evaporation rate in heaped tobacco strips with different thicknesses are analyzed. The results show that: it is feasible to study the drying characteristics of tobacco strips in redrying using a discrete heaped model; there were significant differences in water content, evaporation rate, and temperature in different regions of heaped tobacco strips; the increase in heaping thickness will significantly reduce the uniformity of heat and mass transfer of tobacco strips in the process of convection drying. This model can provide a reference for the study of heat and mass transfer in porous media, such as tobacco strips in the heaping state.

Analysis and modeling of pitaya slices in a heat pump drying system

Abstract The objective of this article was to investigate the drying kinetics, effective moisture diffusivity, and quality of pitaya in the heat pump drying process. The experiment was conducted at a drying temperature of 50–70°C, slice thickness of 8–10 mm, and a relative humidity of 10–30%. The results showed that the heat pump drying of pitaya was a deceleration process. The drying temperature has the greatest influence on the drying rate. The drying time decreased by 28.57% with the drying temperature increased from 50 to 70°C, while that increased the least by 12% with the slice thickness dropped from 10 to 8 mm. Six drying models were analyzed comparatively based on experimental data, and calculations indicated that the Avhad and Marchetti model could better describe the moisture migration law during the heat pump drying process of pitaya. The optimal drying kinetics model was established to predict the change of moisture content under different drying conditions, and the average error of the model compared with the experimental values was 5.56%. In addition, the effective moisture diffusivity of pitaya ranged from 6.4167 × 10−10 to 9.8156 × 10−10 m2/s, and the drying temperature had a remarkable influence on the effective moisture diffusivity while the slice thickness had the least. According to the Arrhenius equation, the drying activation energy of pitaya under the experimental conditions was 19.628 kJ/mol. Moreover, the effect of drying temperature on browning degree and surface microstructure was also analyzed. The conclusions of this article provide theoretical support for the analysis of water migration laws and the optimization of the pitaya heat pump drying process.

Basic Parameters of Medical Textile Materials for Removal and Retention of Exudate from Wounds

The article focuses on predicting the properties of textile materials intended for the treatment of wounds. The main requirements for medical textile materials for liquid transportation were identified. Exudate from wounds and therapeutic fluids from a dressing must move through material with the necessary efficiency. This ensures that unwanted substances are removed from the wound and the necessary moisture is maintained. These requirements can be provided using a mathematical model of the process. Such a model can be substantiated by solving a non-linear differential diffusion equation. For this purpose, the function of changing the moisture content inside a textile material was approximated using a polynomial function that satisfies the boundary conditions. This approximation made it possible to reduce the problem to the solution of an ordinary differential equation with respect to time. The obtained analytical solution of the change in moisture content with respect to time and coordinate includes two diffusion constants. The results of macro-experiments, together with analytical results, made it possible to determine the diffusion coefficient and the nonlinearity coefficient in an explicit form. The results made it possible to predict the moisture content at a given point of textile material at any given time, the total amount of absorbed liquid and the intensity of absorption. The resulting function can recommend the geometric and physical parameters of medical textile materials for the treatment of wounds with a given intensity of exudate sorption.

Prediction of Apple Slices Drying Kinetic during Infrared-Assisted-Hot Air Drying by Deep Neural Networks.

The effects of temperature, air velocity, and infrared radiation distances on the drying characteristics and quality of apple slices were investigated using infrared-assisted-hot air drying (IRAHAD). Drying temperature and air velocity had remarkable effects on the drying kinetics, color, total phenol content, total flavonoid content, and vitamin C content (VCC) of apple slices. Infrared radiation distance demonstrated similar results, other than for VCC and color. The shortest drying time was obtained at 70 °C, air velocity of 3 m/s and infrared radiation distance of 10 cm. A deep neural network (DNN) was developed, based on 4526 groups of apple slice drying data, and was applied to predict changes in moisture ratio (MR) and dry basis moisture content (DBMC) of apple slices during drying. DNN predicted that the coefficient of determination (R2) was 0.9975 and 1.0000, and the mean absolute error (MAE) was 0.001100 and 0.000127, for MR and DBMC, respectively. Furthermore, DNN obtained the highest R2 and lowest MAE values when compared with multilayer perceptron (MLP) and support vector regression (SVR). Therefore, DNN can provide new ideas for the rapid detection of apple moisture and guide apple processing in order to improve quality and intelligent control in the drying process.

Delayed root water supply result in spring dieback of Cabernet Sauvignon in northern China

Cabernet Sauvignon (Vitis vinifera) is one of the main wine-making varieties in the world. Its budding time is late, and cane dieback often occurs in northern China. In order to analyze the causes of shoot drying death of Cabernet Sauvignon in spring, the water supply capacity of the roots of Cabernet Sauvignon and Early-ripening Kyoho and the dynamic changes in the respiration metabolism of roots and buds during the ecodormancy were studied. Additionally, the effects of rootstock SA15 grafting on the sap flow and moisture content changes of Cabernet Sauvignon canes were investigated and the expression of root respiration related genes at different temperatures during the ecodormancy after rootstock SA15 grafting was analyzed. The results showed that compared with Early-ripening Kyoho, the xylem sap flow intensity of Cabernet Sauvignon was low and unstable during the ecodormancy, the roots water reached the peak later, and changes in the respiratory pathways and the accumulation of soluble sugar occurred slowly. The peak of the activity of the respiratory pathways in the Cabernet Sauvignon buds occurred significantly earlier than that of the roots. Compared with self-rooted vines, the peak in the sap flow of Cabernet Sauvignon canes grafted on rootstock SA15 occurred 24 days earlier, and the recovery times of the total water content and free water content occurred earlier. It also increased the roots respiration intensity and the expression of key enzymes of roost respiration under low temperature. In summary, Cabernet Sauvignon insufficient water supply capacity, resulting in difficulty replenishing the water lost from the canes in time and ultimately leading to spring dieback of Cabernet Sauvignon canes. The moisture recovery time of Cabernet Sauvignon canes can be increased by grafting them on rootstock SA15 to prevent the occurrence of spring dieback.

Oilseed rape (Brassica napus L.) potential to remediate Cd contaminated soil under different soil water content

Changes in soil moisture content accompanying ongoing climate change are expected to affect plant growth and contaminants behaviour in the soil. The study was aimed at investigating soil water content impact on the energy crop oilseed rape (Brassica napus L.) efficiency to remediate Cd contaminated soil (1–250 mg kg−1). B. napus growth, Cd accumulation and removal efficiency were evaluated under optimal, reduced and elevated soil water content (SWC). B. napus showed good tolerance to Cd contamination and ability to phytoextract Cd from the soil. Cd accumulation in oilseed rape increased with Cd soil concentration, whereas removal efficiency was regulated by rape growth and Cd soil concentrations. B. napus has demonstrated good efficiency to cope with low and moderate Cd pollution (with tolerance index TI > 0.69), while high Cd soil pollution had a highly significant adverse impact on plant growth (growth was reduced up to 90%) resulting in low Cd removal efficiency. SWC governed plant growth, Cd accumulation and removal from the soil. Oilseed rapes grown under elevated SWC were of higher biomass (18%) compared to those grown under reduced SWC though the detrimental effect of Cd was more severe at elevated SWC. Reduced SWC led to decreased Cd uptake, conversely elevated SWC promoted Cd uptake. The optimal SWC ensures the highest Cd removal efficiency, whereas soil water deficit or excess restricts B. napus potential to remove Cd from the soil and prolongs remediation.

Influence of Microwave and Traditional Smoked Drying Method on the Protein and Moisture Content of Puntius sophore

Drying of fish is a traditional method for storing fishes for long periods without any significant damages. Effects of two smoking and microwave drying on moisture and protein content of fish (Puntius sophore) was studied to determine the benefits of preserving and retaining the protein content of fish. Collected fishes were dried in traditional smoking method for about 12 hours and using microwave drying method at different power levels of 140W, 280W and 560W for different time period. The moisture and protein content of raw fish was found to be 70.78±2.2% and 18.78±1.06 mg/g wet weight respectively. The changes in moisture and protein content in the two different drying methods was found to be significant (p&lt;0.05). With increase in microwave temperature moisture content decreases and protein content increases. The results showed that microwave-drying method could be used for preservation of fish and make the product commercially available.

Shelf Life Prediction and Kinetics of Quality Changes in Pineapple (Ananas comosus) Varieties at Different Storage Temperatures

Shelf life estimation is an important factor to predict the freshness of fruits. This study aimed to investigate the shelf life and the changes in the physicochemical properties of three different pineapple varieties, namely MD2, Josapine, and Morris stored at 5, 10, and 25 °C. The effect of storage temperature on pineapple changes in total soluble solids, pH, moisture content, firmness, and colour was evaluated for 21 days of the storage period. It was revealed that different storage temperatures have a significant effect on the shelf life and quality of different pineapple varieties. The firmness and moisture content showed high regression coefficients, hence were used for the shelf life prediction of pineapple based on kinetic models. By using first-order kinetics, the coefficient of determination (R2) values for quality changes in pineapples ranged from 0.893 to 0.992. The results also demonstrated that the samples stored at 10 °C had the longest shelf life in relation to the changes in firmness and moisture content of the fruit. The findings indicated that shelf life estimation plays an important role to improve the quality preservation of fresh fruits and vegetables during storage.