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Terbium-based coordination polymer (Tb-CP) microspheres with diameters ranging from 0.8 to 1.5 μm were prepared from Tb(NO3)3and 2-nitroterephthalic acid at 160 °C for 6 h. Their composite film with polymethyl methacrylate was prepared by spin-coating method. The products were fully characterized by SEM, TEM, PXRD, TG, FT-IR, and PL. Eu3+-doped Tb-CP microsphere and its film were prepared and their luminescent properties were investigated. It turns out that the hetero-metal CPs only exhibits the characteristic emission peak of Eu3+, indicating metal-to-metal charge transfer from the Tb3+to Eu3+centers.

We performed systematic experiments on the synthesis of layered crystal α-ZrP and revealed the control of size, aspect ratio and size polydispersity of disk-shaped crystals. The growth of the disks is mediated by oriented attachment, taking place continuously throughout the hydrothermal treatment between various sized disks. The master of the synthesis of layered crystals will contribute to various applications such as the nanocomposites and liquid crystals.

In 2002, Lee, Hwang, and Yang proposed a verifier-free remote user authentication scheme using smart cards. Their scheme is efficient because of mainly using cryptographic hash functions. However, we find that Lee-Hwang-Yang's scheme is not reparable once the user's permanent secret is compromised and is vulnerable to a privileged insider's attack. Furthermore, it lacks the user eviction mechanism. In this paper, we first show the weaknesses of Lee-Hwang-Yang's scheme, and then compare Lee-Hwang-Yang's scheme with three similar schemes.

In 2001, Lin, Sun, and Hwang proposed a strong-password authentication protocol, OSPA, which was later found to be vulnerable to a stolen-verifier attack and a man-in-the-middle attack. Recently, Lin, Shen, and Hwang [10] proposed an improved protocol of OSPA and showed that the improved protocol can resist the guessing attack, the replay attack, the impersonation attack, and the stolen-verifier attack. Herein, we show that their protocol is still vulnerable to a replay attack and a denial-of-service attack.