• Journal of the Semiconductor & Display Technology
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• v.19 no.1
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• pp.29-35
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• 2020

The cure characteristics of three kinds of naphthalene type epoxy resins(NET-OH, NET-MA, NET-Epoxy) with a 2-methyl imidazole(2MI) catalyst were investigated for preparing sheet epoxy molding compound(SEMC) for wafer level package(WLP) applications, comparing with diglycidyl ether of bisphenol-A(DGEBA) and 1,6-naphthalenediol diglycidyl ether(NE-16) epoxy resin. The cure kinetics of these systems were analyzed by differential scanning calorimetry with an isothermal approach, and the kinetic parameters of all systems were reported in generalized kinetic equations with diffusion effects. The NET-OH epoxy resin represented an n-th order cure mechanism as like NE-16 and DGEBA epoxy resins, however, the NET-MA and NET-Epoxy resins showed an autocatalytic cure mechanism. The NET-OH and NET-Epoxy resins showed higher cure conversion rates than DGEBA and NE-16 epoxy resins, however, the lowest cure conversion rates can be seen in the NET-MA epoxy resin. Although the NETEpoxy and NET-MA epoxy resins represented higher cure reaction conversions comparing with DGEBA and NE-16 resins, the NET-OH showed the lowest cure reaction conversions. It can be figured out by kinetic parameter analysis that the lowest cure conversion rates of the NET-MA epoxy resin are caused by lower collision frequency factor, and the lowest cure reaction conversions of the NET-OH are due to the earlier network structures formation according to lowest critical cure conversion.

• Journal of Korean Neurosurgical Society
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• v.49 no.5
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• pp.299-301
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• 2011

A case of a symptomatic spinal extradural meningeal cyst (SEMC) in Klippel-Trenaunay syndrome (KTS) is introduced. A 38-year-old woman presented with right L2 radiculopathy. She underwent operations for varicose veins in both her lower extremities. She had port-wine nevi on her trunk and extremities. The edematous change in both legs had waxed and waned. Magnetic resonance imaging showed an $11.8{\times}13$ mm extradural meningeal cyst growing through the intervertebral foramen in L2-3. Multiple meningeal cysts were located in the dorsal aspect of the spinal cord from T3 to T10. A $5.8{\times}6.2$ mm cyst was also found in left pleural cavity. The extradural meningeal cyst was completely excised and the preoperative symptom was improved. KTS is a congenital disorder due to a mesodermal abnormality, which may predispose the dura to weakness. The SEMC may occur through the dural defect or weakened point.