“Vacuum and Surface Science” is an academic journal published by The Japan Society of Vacuum and Surface Science. The first issue was published in January, 2018. The predecessor journals are “Journal of the Vacuum Society of Japan (JVSJ)” and “Hyomen Kagaku (Journal of the Surface Science Society of Japan)”. The journal is aiming to expand into new fields while following the article types published in the predecessors. The journal starts from Vol. 61, taking over the volume number of the long history of JVSJ.
Predecessors ▶ Hyomen Kagaku (The Journal of Surface Science Society of Japan) Vol. 1 (1980) to Vol. 38 (2017) Online ISSN : 1881-4743, Print ISSN : 0388-5321 ▶ Journal of the Vacuum Society of Japan Vol. 51 (2008) to Vol. 60 (2017) Online ISSN : 1882-4749, Print ISSN : 1882-2398
Other predecessors (JVSJ is a successor of following journals.) ▶ Shinku (Vacuum) Vol. 1 (1958) to Vol. 50 (2007) Online ISSN : 1880-9413, Print ISSN : 0559-8516 ▶ Shinku Kogyo (Vacuum Industry) Vol. 1 (1954) to Vol. 5 (1958) Online ISSN : 1883-7174 ▶ Shinku Gijutsu (Vacuum Technolgoy) Vol. 1 (1950) to Vol. 8 (1957) Online ISSN : 1883-7182
Three types of semi-empirical equation for calculating the gas flow rate in a cylindrical tube of arbitrary length-to-diameter ratio are proposed. The solutions of these equations cover all flow regimes from molecular flow to critical flow or subcritical flow via intermediate flow, viscous laminar flow, and turbulent flow. In addition, the calculation procedure is straightforward because it does not require selecting a suitable equation based on the Knudsen number, Reynolds number, and Mach number. Comparing the solutions of the proposed equations with reported results from experiments and computer simulations shows good agreement within 30%.
Yasuyuki YOKOTA, Norihiko HAYAZAWA, Bo YANG, Emiko KAZUMA, Francesca C. I. CATALAN, Yousoo KIM
Microscopic studies on electrolyte solution / electrode interfaces provide the most fundamental information not only for understanding the electric double layer formed at the interfaces but also for designing sophisticated electrochemical (EC) devices. In this study, we developed tip-enhanced Raman spectroscopy (TERS), which is based on an electrochemical scanning tunneling microscope (EC-STM), and demonstrated electrochemical TERS (EC-TERS) measurements of benzenethiol monolayers on Au(111). A specially-designed cell enables us to carry out reproducible EC, EC-STM, and EC-TERS measurements, which indicates consistent results among these techniques for the oxidative desorption of the benzenethiol monolayers.
Hiroshi TOSHIYOSHI, Hiroaki HONMA, Hiroyuki MITSUYA, Gen HASHIGUCHI
Electret or permanent electrical charge is used as a part of mechano-electric energy conversion system for vibrational energy harvesting device. Microscopic capacitors are produced by silicon micromachining or MEMS (microelectromechanical systems) fabrication process, and the surfaces are turned into impurity-rich silicon oxide, which is later processed to make an electret by displacing the impurity ions by the same mechanism as the anodic bonding. The built-in potential of the electret is used to produce electrical current through the electrostatic induction when the movable electrode is periodically shaken by the external vibrations. In this article, the fabrication processes for the electret as well as the MEMS vibrational energy harvester are discussed. The fundamental characteristics of the energy harvesters are reported, along with a demonstration result as an autonomous powerpack for an IoT (internet-of-things) type wireless sensor node.
Soil is defined as a mixture of weathering products of rocks (sand, silt, and clay) and humus (or soil organic matter) derived from plant or animal. World soils are divided into 12 groups and their distribution is not uniform. Soil degradation includes soil acidification in humid region, salinization in arid regions, and loss of soil organic matter in both regions. Minimum tillage or optimized fallow systems can minimize loss of soil organic matter and improve soil fertility. Understanding of complex soil system is required for food supply and human survival.
Digital Annealer developed by Fujitsu is a new architecture to solve “combinatorial optimization problems” at high speed with digital circuit inspired by quantum phenomena. The features are stable operation with digital circuit at room temperature, easy miniaturization, and easy mapping more complex problems with a fully-connected architecture. The Digital Annealer is easy to apply actual problems and contributes to customers in a wide range of businesses, including drug discovery, chemistry, manufacturing, transportation, finance, and logistics. In this article, we explain the fundamental of the Digital Annealer including the speedup technique. We also introduce an application to the material development using the Digital Annealer. The Digital Annealer is used to evaluate the structural similarity of the flavor molecules. We found that the molecules with high structural similarity show a similar flavor. We also extracted the common substructure of molecules having the similar flavor, which is considered to be the key structure of the flavor.