Ordered graphane nanoribbons synthesized via high-pressure diels-alder polymerization of 2,2'-bipyrazine

Li, F.*; Tang, X.*; Fei, Y.*; Zhang, J.*; Liu, J.*; Lang, P.*; Che, G.*; Zhao, Z.*; Zheng, Y.*; Fang, Y.*; et al.

Journal of the American Chemical Society, 147(17), p.14054 - 14059, 2025/04

https://doi.org/10.1021/jacs.5c03116

We synthesized a crystalline graphane nanoribbon (GANR) via pressure-induced polymerization of 2,2'-bipyrazine (BPZ). By performing Rietveld refinement of in situ neutron diffraction data, nuclear magnetic resonance spectroscopy, infrared spectra, and theoretical calculation, we found that BPZ experienced Diels-Alder polymerization between the stacked aromatic rings, and formed extended boat-GANR structures with exceptional long-range order. The unreacted -C=N- groups bridge the two ends of the boat, and ready for further functionalization. The GANR has a bandgap of 2.25 eV, with booming photoelectric response (/ =18.8). Our work highlights that the high-pressure topochemical polymerization is a promising method for the precise synthesis of graphane with specific structure and desired properties.

Characteristics of high repetition rate wavelength tunable solid state laser for real time laser monitoring system

Maruyama, Yoichiro; Kato, Masaaki

JAERI-Research 2002-040, 15 Pages, 2003/02

JAERI-Research-2002-040.pdf:1.05MB

As a tunable laser source for the study of real time LIDAR techique to detect some trace impurities in atmosphere, a dye laser has been employed. As a dye laser is difficult to handle, it is considered that the dye laser may not be used as a practical light source. A tunable solid stat laser composed of an optical parametricc oscillaotr (OPO) which has a wider wavelength range is one of the promising tunable light sources, however, there is no OPO with high repetition rate and large pulse energy. Therefore high repetition rate lasing characteristics of OPO are studied. In this experiment, -Barium Borate (BBO) crystal is utilized as a gain meduim of OPO and pumped by the second harmonic of Nd:YAG laser with the pulse repetition rate of 0.5 kHz. The threshold pumping peak power for BBO-OPO is around 16 MW/cm. Maximum OPO average output power of around 5.4 W is obtained with the power conversion efficiency of around 45%. The averege output power of OPO is increasing with the pumping power and undesirable thermal effects are not observed.

Recent developments of the ISOLDE laser ion source

J.Lettry*; R.Catherall*; V.Fedoseyev*; G.J.Focker*; G.Huber*; O.C.Jonsson*; E.Kugler*; Koizumi, Mitsuo; U.Koester*; V.I.Mishin*; et al.

Review of Scientific Instruments, 69(2), p.761 - 763, 1998/02

https://doi.org/10.1063/1.1148978

no abstracts in English

Production of Ir Source for Radiotherapy

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JAERI-M 9817, 27 Pages, 1981/11

JAERI-M-9817.pdf:1.13MB

no abstracts in English