Microencapsulation of imidazole curing agent by solvent evaporation method using W/O/W emulsion

The epoxy–imidazole resin system is used to form the anisotropic conducting film. The latent character of the system is very significant. In this study, imidazole (Im) or 2‐methylimidazole (2MI) was encapsulated for the latent curing system to use in the reaction of epoxy resin. Polycaprolactone was used as a wall material, and the solvent evaporation method was used to form the microcapsule using W/O/W emulsion. The shelf life of the microcapsules was studied for the epoxy resin, and the curing behavior of the microcapsules for epoxy resin was examined using a differential scanning calorimeter. The curing times at 150 and 180°C were estimated using an indentation method. The microcapsules of Im or 2MI exhibited a long shelf life for epoxy resin. When comparing the results of the previous methods with the results of this study using the W/O/W emulsion, finer microcapsules were formed and the microcapsule has longer shelf life. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98341/1/38767_ftp.pd

High-accuracy skin lesion segmentation and size determination

Title from PDF of title page (University of Missouri--Columbia, viewed on June 11, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. Yi ShangIncludes bibliographical references.M. S. University of Missouri--Columbia 2011."December 2011"Melanoma is one of the most common skin cancers. 5% of all cancer cases that occur in a year are cases of skin cancer and many people die each year by melanoma because of late recognition. Moreover, the number of new cases of melanoma in the United States has been increasing for at least 30 years. Fortunately, this melanoma is highly curable if it is detected early. In order to detect skin lesions, the automated skin lesion segmentation and diagnosis system on the Android system is an outstanding program to use. In this thesis, there are 4 functionalities, which include: camera data collecting, image processing, feature calculation, and classification. With these processes, an image is captured and is converted to a grey image. After a grey image is created, a skin lesion contour is found by OpenCV functions, cvFindContour() and cvWatershed(). When the contour is found, the features color, shape, and size of the lesion are extracted in order to classify whether the lesion is benign or malignant by using the KNN classifier. The goals and achievements of this thesis are to implement a function that captures images with the Android using camera properties, improve image segmentation and size estimation based on the previous prototype system on the Android platform with OpenCV. An image can be captured by a capturing function in this thesis and can be saved in a jpg file and a data xml file, which are used for image processing and camera features. In image processing, the watershed function is used instead of cvThreshold function, which is on the previous prototype system, so that the number for the threshold value is no more needed and the system can find the most method contour instead of finding several contours as it does in the previous system. In size estimation, two methods, which are reference method and camera distance method, are used. Reference method is when the system can estimate the area of a lesion by comparing reference pixels and lesion pixels. Camera distance method is when the system can estimate the area of a lesion according to camera distance properties, which are near, optimal, and far camera distance values. With these two methods, the system can estimate real area of a lesion without rulers instead of counting the number of pixels. Contour detection is improved to 98%. Reference size estimation and camera focus distance size estimations are 1.04% and 8.23

Low-cost, open-source contact angle analyzer using a mobile phone, commercial tripods and 3D printed parts

Measurement of contact angle is important in many areas of science and engineering research. Contact angle analyzers are however not easily accessible due to their expensive cost, which hinders their use in research and also in education. In this study we propose a low-cost contact angle analyzer that can be assembled with 3D printed parts. Mobile phone is used for imaging, and the image is analyzed using an open-source ImageJ plugin. Commercial camera tripods are used as platform that provides movement in many degrees of freedom, which are important in leveling of the substrate and proper imaging of droplets. We utilize the tripods to build imaging modules, sample plate module and volume metering module, each of which perform distinct tasks. Especially, we characterize the usefulness of the volume metering module, which helps users dispense same volume of liquid to reduce human error during measurement. The cost of an analyzer is $255.10, which is an order of magnitude lower compared to commercial products. With the advancement in open source software and upgrades in the hardware modules, we expect that the proposed contact angle analyzer to have a positive impact in resource limited research labs and educational environments