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Research paper : Innovative electron microscope for light-element atom visualization (Y. Sato et al.)−181−Synthesiology - English edition Vol.4 No.3 (2012) Takeshi TomitaRecieved his B.S. from Kyushu University in 1972. He joined JEOL Ltd. in 1972, and is currently a member of EM Technical Group 1, EM Business Unit, JEOL. In this project, he is mainly in charge of development of the low-voltage field emission guns.Toshikatsu KaneyamaReceived his M.S. from Tohoku University in 1987. He joined JEOL Ltd. in 1987, and is currently the general manager of EM Technical Group 1, EM Business Unit, JEOL. In this project, he is responsible for management of developing the low-voltage electron microscopes.Yukihito KondoReceived his M.E. from Tokyo Institute of Technology in 1978. He joined JEOL Ltd. in 1979, and is currently the technical general manager of EM Business Unit. In this project, he is responsible for general management of developing the low-voltage electron microscopes.Kazutomo SuenagaReceived his Ph.D. in materials science from the University of Tokyo in 1994. He was a postdoctoral fellow at Ecole Nationale Superieure des Mine de Paris, France (1994-1997), and at the Solid State Physics Laboratory in the University Paris-Sud, France (1997-1998). Then he joined the Japan Science and Technology Corporation (JST) as a researcher (1998-2001). He has been a team leader at Nanotube Research Center of AIST since 2001, and also a prime senior researcher at AIST since 2010. He is responsible for administration of this project, and also in charge of application experiments of the low-voltage electron microscopes.Discussions with Reviewers1 Author contributionsQuestion (Shuji Abe, Evaluation Department, AIST; Toshimi Shimizu, Nanotechnology, Material and Manufacturing, AIST)This paper is co-written by eight authors, and mainly presents the results of the collaboration between AIST and JEOL. We understand that this work has been carried out as a part of the JST-CREST joint project in which AIST, JEOL and NIMS are participating. We expect author profiles are provided above, but can you explain the contributions of these organizations and members?Answer (Yuta Sato)This project has been carried out through collaboration between JEOL, NIMS and AIST. Eight researchers from each of JEOL and AIST, and two from NIMS have participated in this project (in total, excluding technical assistant staffs). In order to realize unprecedented low-voltage electron microscopes within a given period, we have had to combine our expertise in the fields such as theory of electron microscopy and spectroscopy, equipment, materials and phenomena to observe (solid-state physics, material science, nano-science, biology, etc.). The JEOL team, as a microscope manufacturer, developed each component, constructed two microscopes and examined their performances. The NIMS and AIST teams took charge of preliminary study for planning this project, the application of the low-voltage microscopes to scientific observation, and reference experiments using conventional microscopes. We described these contributions in Chapter 2 of the revised manuscript. 2 Competitors’ projectsQuestion (Toshimi Shimizu)This paper shows that the authors’ group has pioneered in developing low-voltage electron microscopes equipped with chromatic and/or spherical aberration correctors. In chapter 6, however, it is also stated that low-voltage microscopes are now regarded as the main advanced forms of electron microscopy, and the competition between full-scale projects is intensifying worldwide. It is not clear to me whether such a world trend originated from the authors’ project, or whether it independently emerged as integration of newly developed elemental technologies. I think additional description on the world trend and on the benchmarks of this project is effective in presenting more clearly the features of this project. Answer (Kazutomo Suenaga)In our revised manuscript, we emphasized that this is the first project in the world to construct totally new low-voltage electron microscopes. In addition, we stated that a foreign group also started developing low-voltage microscopes based on a similar concept just after we launched this project, and some other existing projects decided to cover low-voltage systems as additional targets. We presume that the performance of our first experimental microscope, which is the world’s first system specially designed for low acceleration voltages, has affected the competitors’ projects both directly and indirectly. Although it is difficult at this stage to specify how far such effects have spread over, we revised chapter 6 to refer to the world trend according to your comment.3 “Soft matter”Question (Shuji Abe)I find that the term “soft matter” often appears in this paper, while the application of the low-voltage microscopes is currently focused on carbon nano-materials. In my opinion, carbon nano-materials themselves are not classified as soft matter, because they are known as robust materials. For future application of your low-voltage microscopes to real soft matter such as bio-materials, do you think their performance is high enough even at this stage, or further technical improvement is necessary?Answer (Yuta Sato)Low-voltage observation of soft matter is a final goal of our project. In our preliminary experiments, we used carbon nano-materials as test specimens to examine the effect of low acceleration voltages. CNTs and graphene are known to possess high mechanical strengths, and expected to be more stable under electron-beam irradiation than soft matters in general. Nevertheless, we had to give up many scientifically important experiments on these materials in the past, due to serious irradiation-induced damages occurring in conventional microscopes even at relatively low voltages such as 120 and 80 kV. In this project, we have achieved drastic reduction

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