MingDao University

About: MingDao University is a education organization based out in Bitou, Taiwan. It is known for research contribution in the topics: Thin film & Coating. The organization has 557 authors who have published 903 publications receiving 17915 citations.

Thermal stability behaviors of Cr(N,O)/CrN double-layered coatings by TGA/DTA analysis

Abstract: In this study, Cr(N,O)/CrN double-layered coatings were synthesized using the cathodic arc deposition (CAD) process. CrN film was first deposited onto a substrate as an interlayer to ensure better adhesion, and Cr(N,O) film was subsequently deposited on top of the CrN layer as the surface layer. Variation in the Cr(N,O) coating composition was achieved through changing the O 2 /N 2 flow ratio during the last stage of processing. Phase structure, chemical composition, and morphology of the resulting coatings were analyzed and observed using the X-ray diffractometer, Auger electron spectrometer and SEM. In addition, oxidation behavior of the coatings was investigated using TGA/DTA methods. The tests were carried out by increasing temperature up to 1000 °C in ambient air. With the introduction of oxygen gas during the CAD process, a superficial layer was produced in the Cr(N,O) constituent containing CrN and Cr 2 O 3 phases. The formation of the oxide phase attributed to the reaction of chromium and oxygen was more favorable than that of chromium and nitrogen. The results also showed that Cr(N,O)/CrN double-layered coatings exhibited superior oxidation resistance at elevated temperature than that of CrN single-layer coated specimen (870 °C vs . 750 °C).

Ultrastructural observation of oocytes in six types of stony corals

Abstract: In this study, the ultrastructure of the oocytes of 6 types of scleractinian corals was observed by transmission electron microscopy (TEM). Moreover, histological and ultrastructural analyses were performed to improve our understanding of the organelles involved in coral oocyte formation. In all 6 stony coral species, the microvilli were tubular and directly grew from the surface of the oocyte membrane; yolk bodies, lipid granules, and cortical alveoli accounted for most of the volume inside the oocytes, suggesting that they are associated with energy storage and buoyancy. Clear differences were observed in the size of yolk bodies and lipid granules in the oocytes of the 6 stony coral species, which occupied approximately 55%-80% of the inner space of the oocytes. Galaxea fascicularis exhibited the largest lipid granule volume, but the oocytes contained only an average number of 12.45 lipid granules per unit area. Only Montipora incrassata oocytes contained symbiotic algae. The smallest size and proportion of lipid granules in M. incrassata oocytes may be attributed to the presence of symbiotic algae and large yolk bodies, which may help oocytes produce energy and function as a nutritional source. This study is crucial for improving the understanding of the basic biology of coral reproduction, and the ensuing datasets is critical for conservation-oriented studies seeking to cryopreserve corals during these times of dramatic global climate change.

The compare organic farm and conventional farm to improve sustainable agriculture, ecosystems, and environment

Abstract: Current excessive environmental developments result in a growing number of artificial facilities, and the impact of human activities leads to the destruction and loss of many natural habitats, while the remaining habitats are isolated and fragmented, and are increasingly replaced by more artificial facilities. Today’s agriculture in Taiwan generally adopts pesticides and other means of farming, and the government encourages the use of cement as a ridge. Although a cement ridge can be easily used by farmers, will reduce the amount of weeds, and improve agricultural production, its environmental costs may be higher. Therefore, this study mainly probes into the differences in ecological abundance between organic farms with a mud ridge and conventional farms with a cement ridge. This study employs field investigation, records the species found by camera, and observes and analyzes the abundance and the relationship between the growth and decline of the species in these two different environments. According to the research results, biological species occur throughout the year; however, the numbers of species in organic farms are nearly 3 times higher than that of conventional farms: 7 more types of insects, 1 more type of arachnid, and 7 more types of birds, and the number of a single species is 20 times higher. This study can be used as a reference and basis for engaging in agricultural production and planning farming areas when considering environmental and ecological conservation in the future.

A pilot study of the color performance of recycling green building materials

Abstract: The concept of green building integrates a variety of strategies during the design, construction and operation of building projects. The use of green building materials represents one very crucial strategy during the design and construction of a building. Recycling green building materials refer to those building materials reproduced from other materials, namely, reclaim the waste or discarded materials to produce the building materials. In Taiwan, gypsum boards are widely used in the building industry as facing materials for walls and ceilings due to their very good mechanical and thermal properties, as well as fire endurance. The goal of this study is to develop a new recycling green building material which could reuse the daily waste materials, color changeable and give inspiration to improve the characters of green building materials . In this study, six waste materials in our daily lives were mixed with the allochroic powder and gypsum powder to create thermochromic face bricks. The experiment modules were Groups A, B, C, and D, and mixed with allochroic powders of different specifications. The findings showed that Group C had the most significant RGB variation. In terms of the G value of Group C, the variations of the six materials were wood chips 81.9%>, newspaper 78%>, concrete 75.6%>, fallen leaves 66.6%>, iron powder 59.2%>, and silt 50.9%. In conclusion, allochroic faced bricks can be applied to both interior and exterior walls of different types of buildings in the future, thus, the buildings have different colors at different temperatures and times, cater to the changeful effects of future architectural appearances. Regarding the landscape, building and interior designers can construct artistic creations of shell collages.

Heat Transfer in a Porous Electrode of Fuel Cells

Abstract: The thermal-fluid behaviors in a porous electrode of a proton exchange membrane fuel cell (PEMFC) in contact with an interdigitated gas distributor are investigated numerically. The porous electrode consists of a catalyst layer and a diffusion layer The heat transfer in the catalyst layer is coupled with species transports via a macroscopic electrochemical model. In the diffusion layer, the energy equations based on the local thermal nonequilibrium (LTNE) are derived to resolve the temperature difference between the solid phase and the fluid phase. Parametric studies include the Reynolds number and the Stanton number (St). Results show that the wall temperature decreases with increasing Stanton number. The maximum wall temperatures occur at the downstream end of the module, while the locations of local minimum wall temperature depend on the Stanton numbers. Moreover, the solid phase and the fluid phase in the diffusion layer are thermally insulated as St « 1. The diffusion layer becomes local thermal nonequilibrium as the Stanton number around unity. The porous electrode is local thermal equilibrium for St» 1. Finally, the species concentrations inside the catalyst and diffusion layers are also provided.