The Experts below are selected from a list of 4995 Experts worldwide ranked by ideXlab platform
A M Donald - One of the best experts on this subject based on the ideXlab platform.
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2003 Use of environmental scanning electron microscopy to image the spore adhesive of the marine alga Enteromorpha in its natural hydrated state
2020Co-Authors: James A. Callow, Maureen E. Callow, M P Osborne, F Baker, A M DonaldAbstract:Abstract The environmental scanning electron microscope (ESEM) has been used to image the adhesive secreted by zoospores of the marine alga Enteromorpha as they settle on a surface, under natural, hydrated conditions. Results reveal a featureless, swollen gel-like adhesive pad, in contrast to the fibrillar character of the adhesive when imaged by standard SEM. At high spore densities the adhesive is confluent. Dynamic hydration/dehydration events were followed by changing the water vapour pressure in the sample chamber. Rapid hydration and swelling were observed indicating a very Hygroscopic Material. Adhesive footprints were detected when surfaces from which spores had been removed by water jetting were examined.
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use of environmental scanning electron microscopy to image the spore adhesive of the marine alga enteromorpha in its natural hydrated state
Colloids and Surfaces B: Biointerfaces, 2003Co-Authors: James A. Callow, Maureen E. Callow, M P Osborne, F Baker, A M DonaldAbstract:The environmental scanning electron microscope (ESEM) has been used to image the adhesive secreted by zoospores of the marine alga Enteromorpha as they settle on a surface, under natural, hydrated conditions. Results reveal a featureless, swollen gel-like adhesive pad, in contrast to the fibrillar character of the adhesive when imaged by standard SEM. At high spore densities the adhesive is confluent. Dynamic hydration/dehydration events were followed by changing the water vapour pressure in the sample chamber. Rapid hydration and swelling were observed indicating a very Hygroscopic Material. Adhesive footprints were detected when surfaces from which spores had been removed by water jetting were examined.
Menghao Qin - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and characteristics of Hygroscopic phase change Material: Composite microencapsulated phase change Material (MPCM) and diatomite
Energy and Buildings, 2015Co-Authors: Zhi Chen, Menghao Qin, Jun YangAbstract:This paper prepared a new kind of Hygroscopic phase change Material using MPCM and diatomite. The composite can absorb/release not only thermal heat, but also moisture. The shell Material of MPCM was prepared with methyl triethoxysilane (MTES) by sol-gel method, and a kind of alkane mixture was used as the core Material. The diatomite was used as Hygroscopic Material. The morphology of the microcapsules and the diatomite were measured by the scanning electron microscopy (SEM). The thermal properties of MPCM and the composite MPCM/diatomite Materials (CMPCM) were analyzed with differential scanning calorimetry (DSC). The thermal gravimetric analysis (TGA) was used to study the thermal stability of MPCM and CMPCM. The moisture transfer coefficient and moisture buffer value (MBV) of the diatomite and CMPCM were measured. The DSC results showed that the microcapsules were encapsulated in the SiO2 shell. The TGA results showed that the microcapsules and CMPCM have a good thermal stability. The measurements of the moisture transfer coefficient and moisture buffer value (MBV) of CMPCM, diatomite, gypsum board and wood showed that CMPCM has a better Hygroscopic performance. The Hygroscopic phase change Material can moderate both the indoor temperature and moisture.
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Synthesis and Characterization of Composite Phase Change Material (CPCM) with SiO2 and Diatomite as Endothermal-Hygroscopic Material
Energy Procedia, 2015Co-Authors: Zhi Chen, Menghao QinAbstract:Abstract This paper prepared a kind of CPCM/diatomite composite as Hygroscopic phase change Material. The SiO2 of the CPCM was prepared with tetraethyl orthosilicate with sol–gel method, and a kind of alkane mixture was used as phase change Material (PCM). The diatomite was used as Hygroscopic Material. We used scanning electronic microscope (SEM) to determine the microstructure of the composites. The heat absorbing/solidifying properties and thermal stability of the composites were measured with the differential scanning calorimeter (DSC) and thermo-gravimetric analyzer (TGA). The Hygroscopic properties were also investigated. The measurement results indicated that the composites had good thermal control and Hygroscopic properties.
Zhi Chen - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and characteristics of Hygroscopic phase change Material: Composite microencapsulated phase change Material (MPCM) and diatomite
Energy and Buildings, 2015Co-Authors: Zhi Chen, Menghao Qin, Jun YangAbstract:This paper prepared a new kind of Hygroscopic phase change Material using MPCM and diatomite. The composite can absorb/release not only thermal heat, but also moisture. The shell Material of MPCM was prepared with methyl triethoxysilane (MTES) by sol-gel method, and a kind of alkane mixture was used as the core Material. The diatomite was used as Hygroscopic Material. The morphology of the microcapsules and the diatomite were measured by the scanning electron microscopy (SEM). The thermal properties of MPCM and the composite MPCM/diatomite Materials (CMPCM) were analyzed with differential scanning calorimetry (DSC). The thermal gravimetric analysis (TGA) was used to study the thermal stability of MPCM and CMPCM. The moisture transfer coefficient and moisture buffer value (MBV) of the diatomite and CMPCM were measured. The DSC results showed that the microcapsules were encapsulated in the SiO2 shell. The TGA results showed that the microcapsules and CMPCM have a good thermal stability. The measurements of the moisture transfer coefficient and moisture buffer value (MBV) of CMPCM, diatomite, gypsum board and wood showed that CMPCM has a better Hygroscopic performance. The Hygroscopic phase change Material can moderate both the indoor temperature and moisture.
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Synthesis and Characterization of Composite Phase Change Material (CPCM) with SiO2 and Diatomite as Endothermal-Hygroscopic Material
Energy Procedia, 2015Co-Authors: Zhi Chen, Menghao QinAbstract:Abstract This paper prepared a kind of CPCM/diatomite composite as Hygroscopic phase change Material. The SiO2 of the CPCM was prepared with tetraethyl orthosilicate with sol–gel method, and a kind of alkane mixture was used as phase change Material (PCM). The diatomite was used as Hygroscopic Material. We used scanning electronic microscope (SEM) to determine the microstructure of the composites. The heat absorbing/solidifying properties and thermal stability of the composites were measured with the differential scanning calorimeter (DSC) and thermo-gravimetric analyzer (TGA). The Hygroscopic properties were also investigated. The measurement results indicated that the composites had good thermal control and Hygroscopic properties.
Hang Wan - One of the best experts on this subject based on the ideXlab platform.
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optimal moisture buffering thickness of the Hygroscopic Material layer modeling and derivation
Building and Environment, 2021Co-Authors: Hang Wan, Gongsheng Huang, Sheng Liu, Shiguang FanAbstract:Abstract The indoor humidity level can be passively improved by the Hygroscopic Material without energy consumption. Some studies demonstrate that the moisture buffering capacity (MBC) of the Hygroscopic Material layer is affected by the Material's thickness. There exists an optimal thickness that maximizes the Material's moisture buffering capacity when some Hygroscopic Material is exposed in a specific indoor environment. Some methods have been proposed to determine this optimal moisture buffering thickness (Lopt). However, such methods are primarily based on experimental measurements or numerical simulation. Therefore, optimal moisture buffering thicknesses are approximate values. In this paper, an analytical method was proposed to solve the theoretical Lopt based on the moisture transfer function. Correspondingly, the ideal and practical optimal thickness, which present an ideal situation and a practical situation of the indoor humidity variation, respectively, were theoretically derived and validated using numerical simulations. Moreover, the optimal moisture buffering thicknesses of some conventional building wall Hygroscopic Materials were derived and calculated simply and efficiently via the proposed analytical method. The proposed analytical method is based on the theoretical derivation and has many advantages in terms of computational efficiency and accuracy compared with experimental measurements and numerical simulations.
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development of a simplified dynamic moisture transfer model of building wall layer of Hygroscopic Material
Energy, 2019Co-Authors: Tian Yan, Hang Wan, Zhongwei Sun, Gongsheng HuangAbstract:Abstract Indoor air humidity has a significant impact on indoor air quality, building energy consumption, and equipment performance. Excessively low or high humidity is not good for living and working. Hygroscopic Materials can be used to moderate the indoor air humidity level. This paper presents a simplified dynamic moisture transfer model of building wall layer of Hygroscopic Material, and the parameter identification of the simplified model with genetic algorithm by comparing the frequency characteristics of the simplified model with the theoretic frequency characteristics. The proposed simplified model was validated against the published experimental measurements on the system level. The results show that the predicted moisture flux by the simplified model agrees well with the experimental test. The simplified model was also validated on room level by a common exercise in IEA 41 project. The results show that the simplified model has a good agreement with the analytical solution, within ±2.2% in the case CE1A. In the realistic case CE1B, the model prediction matches the results of these detailed models provided in public literature. The proposed simplified dynamic moisture transfer model can be used in building indoor humidity environment and energy consumption simulation with good accuracy and efficiency.
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Calculation of the maximum moisture buffering thickness of building wall layer of Hygroscopic Material
Building and Environment, 2019Co-Authors: Hang Wan, Zhongwei Sun, Gongsheng HuangAbstract:Abstract Hygroscopic Material can be used to moderate the indoor humidity variation due to its moisture buffering ability. Many studies have been carried out to evaluate the moisture buffering potential of Hygroscopic Materials. However, there is little literature about the optimal thickness of Hygroscopic Material for building design. This paper presents a simple method for determining the optimal moisture buffering thickness (Lopt) at which the Hygroscopic Material has maximum moisture buffering capacity (MBC) at a certain moisture environment. This method involves the calculation of MBC value by using moisture transfer function and Fourier transform. A case study of the clay plaster shows that the MBC firstly increases quickly and then decreases slowly as the Material thickness increases. There exists an optimal thickness at which the MBC is biggest. This method for calculating the Lopt of the Hygroscopic Material layer of building wall is validated against the published experimental measurements. In addition, the proposed simple method is also compared with the experiment-based method and traditional numerical method. The result shows that this method is simple and efficient while keeping high accuracy. This proposed method can be used for the determination of the optimal thickness of Hygroscopic Material in building design stage.
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Development of a moisture transfer calculation method of Hygroscopic Material plate in buildings
Building and Environment, 2018Co-Authors: Hang Wan, Gongsheng HuangAbstract:Abstract Hygroscopic Material could be used to moderate the indoor humidity fluctuation and reduce heating and cooling energy consumption. In order to calculate the moisture transfer between the wall Hygroscopic Material plate and the indoor air quickly and accurately, a simple moisture transfer calculation method coupling moisture transfer function and Fourier transform is proposed and developed. This paper further presents the analytical verification and experimental validation of this method. The analytical verification shows that the average relative error between the model prediction and analytical results under the periodic sinusoidal and rectangular variations of indoor air humidity are 0.2% and 5.2% respectively. An experiment test rig was established to measure the moisture sorption of Hygroscopic Material plate taking silicate calcium plate as a sample. The chamber climate was controlled as expected and two typical real office climates with different moisture load schedule were simulated. Compared with the experimental measurements, the average relative errors of the moisture flux between the model prediction and the measurement are 10.7% for Case 1 and 12.1% for Case 2 respectively. The proposed method has also been validated by published experiment measurements and shows a good accuracy as well as high computationally efficiency. This simple method can be easily applied on moisture sorption calculation of Hygroscopic Materials.
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A Moisture Penetration Depth Model of Building Hygroscopic Material
Procedia Engineering, 2017Co-Authors: Hang Wan, Jiajia GaoAbstract:Abstract Due to the significant impact of indoor humidity on Indoor Air Quality, human comfort and energy consumption, many researchers have investigated the use of various Hygroscopic Materials to moderate indoor humidity levels and save energy. The results show that the indoor relative humidity of the room with Hygroscopic Materials is more stable and moderate. Although many laboratory measurements and numerical simulation studies have been done for Hygroscopic Materials, there is little study on moisture exchange between Materials with limited thickness and indoor air. The EMPD model is widely used due to its fast solution time and reasonable accuracy. However, it is not suitable when the Hygroscopic Material is thin and limited. In this paper, a double effective moisture penetration depth (DEMPD) model is described and developed. An application analysis of the proposed DEMPD model is presented. The results show that the DEMPD model can well simulate the moisture exchange between Hygroscopic Material with limited thickness and indoor air while the traditional EMPD model shows a great deviation.
James A. Callow - One of the best experts on this subject based on the ideXlab platform.
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2003 Use of environmental scanning electron microscopy to image the spore adhesive of the marine alga Enteromorpha in its natural hydrated state
2020Co-Authors: James A. Callow, Maureen E. Callow, M P Osborne, F Baker, A M DonaldAbstract:Abstract The environmental scanning electron microscope (ESEM) has been used to image the adhesive secreted by zoospores of the marine alga Enteromorpha as they settle on a surface, under natural, hydrated conditions. Results reveal a featureless, swollen gel-like adhesive pad, in contrast to the fibrillar character of the adhesive when imaged by standard SEM. At high spore densities the adhesive is confluent. Dynamic hydration/dehydration events were followed by changing the water vapour pressure in the sample chamber. Rapid hydration and swelling were observed indicating a very Hygroscopic Material. Adhesive footprints were detected when surfaces from which spores had been removed by water jetting were examined.
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use of environmental scanning electron microscopy to image the spore adhesive of the marine alga enteromorpha in its natural hydrated state
Colloids and Surfaces B: Biointerfaces, 2003Co-Authors: James A. Callow, Maureen E. Callow, M P Osborne, F Baker, A M DonaldAbstract:The environmental scanning electron microscope (ESEM) has been used to image the adhesive secreted by zoospores of the marine alga Enteromorpha as they settle on a surface, under natural, hydrated conditions. Results reveal a featureless, swollen gel-like adhesive pad, in contrast to the fibrillar character of the adhesive when imaged by standard SEM. At high spore densities the adhesive is confluent. Dynamic hydration/dehydration events were followed by changing the water vapour pressure in the sample chamber. Rapid hydration and swelling were observed indicating a very Hygroscopic Material. Adhesive footprints were detected when surfaces from which spores had been removed by water jetting were examined.