One-pot three-component synthesis of α-amino nitriles catalyzed by nano powder TiO_2 P 25

A simple and efficient method has been developed for the synthesis ofα-amino nitriles from aldehydes,amines and trimethylsilyl cyanide（Me₃SiCN） in the presence of a catalytic amount of cyanuric acid at room temperature.     

Capacity of a Simultaneous Quantum Secure Direct Communication Scheme between the Central Party and Other M Parties

We analyse the capacity of a simultaneous quantum secure direct communication scheme between the central party and other M parties via M＋1-particle GHZ states and swapping quantum entanglement. It is shown that the encoding scheme should be secret if other M parties wants to transmit M ＋ 1 bit classical messages to the centre party secretly. However, when the encoding scheme is announced publicly, we prove that the capacity of the scheme in transmitting the secret messages is 2 bits, no matter how large M is.     

1-Methylimidazole-catalyzed reaction between tosylmethyl isocyanide and dialkyl acetylenedicarboxylates:An efficient synthesis of functionalized pyrroles

An efficient 1-methylimidazole-catalyzed synthesis of dialkyl 2-[(4-methylphenyl)sulfonyl]-1H-pyrrole-3,4-dicarboxylates is described.The reactive 1:1 zwitterionic intermediate formed by the addition of 1-methylimidazole to dialkyl acetylenedicarboxylates is trapped by tosylmethyl isocyanide(TOSMIC) to afford the title compounds in excellent yields.     

Stability and activity of carbon nanofiber-supported catalysts in the aqueous phase reforming of ethylene glycol

Nickel, cobalt, copper and platinum nanoparticles supported on carbon nano-fibers were evaluated with respect to their stability, catalytic activity and selectivity in the aqueous phase reforming of ethylene glycol (230 C, autogenous pressure, batch reactor). The initial surface-specific activities for ethylene glycol reforming were in a similar range but decreased in the order of Pt (15.5 h1 ) >Co(13.0 h1 ) >Ni(5.2 h1 ) while the Cu catalyst only showed low dehydrogenation activity. The hydrogen molar selectivity decreased in the order of Pt (53%)>Co(21%)>Ni (15%) as a result of the production of methane over the latter two catalysts. Over the Co catalyst acids were formed in the liquid phase while alcohols were formed over Ni and Pt. Due to the low pH of the reaction mixture, especially in the case of Co (as a result of the formed acids), significant cobalt leaching occurs which resulted in a rapid deactivation of this catalyst. Investigations of the spent catalysts with various techniques showed that metal particle growth is responsible for the deactivation of the Pt and Ni catalysts. In addition, coking might also contribute to the deactivation of the Ni catalyst.     

不同实验条件对DSC峰形的影响以及相变温度的确定

本文通过深入分析实际的ＤＳＣ过程，阐述了ＤＳＣ曲线上各个特征点以及这些点所对应的物理意义。在理论上分析各种不同的实验条件对ＤＳＣ曲线形状的影响，指出目前在ＤＳＣ分析中所用的确定试样熔点的方法以及用高纯金属ＤＳＣ变曲线上熔融峰峰前沿的斜率修正试样相变温度所存在的问题，指出ＤＳＣ相变曲线刚开始偏离基线的那点所相应试样盒的温度即为试样的熔点，本文还提出了通过提高试样，试样盒以及试样支座之间的热导率，来提