Mitsubishi Chemical Corporation Research Articles

Absolute energy-dependent scintillating screen calibration for real-time detection of laser-accelerated proton bunches.

Laser-plasma accelerators (LPAs) can deliver pico- to nanosecond long proton bunches with ≳100 nC of charge dispersed over a broad energy spectrum. Increasing the repetition rates of today's LPAs is a necessity for their practical application. This, however, creates a need for real-time proton bunch diagnostics. Scintillating screens are one detector solution commonly applied in the field of electron LPAs for spatially resolved particle and radiation detection. Yet their establishment for LPA proton detection is only slowly taking off, also due to the lack of available calibrations. In this paper, we present an absolute proton number calibration for the scintillating screen type DRZ High (Mitsubishi Chemical Corporation, Düsseldorf, Germany), one of the most sensitive screens according to calibrations for relativistic electrons and x rays. The presented absolute light yield calibration shows an uncertainty of the proton number of 10% and can seamlessly be applied at other LPA facilities. For proton irradiation of the DRZ High screen, we find an increase in light yield of >60% compared to reference calibration data for relativistic electrons. Moreover, we investigate the scintillating screen light yield dependence on proton energy since many types of scintillators (e.g., plastic, liquid, and inorganic) show a reduced light yield for increased local energy deposition densities, an effect termed ionization quenching. The ionization quenching can reduce the light yield for low-energy protons by up to ∼20%. This work provides all necessary data for absolute spectral measurements of LPA protons with DRZ High scintillating screens, e.g., when used in the commonly applied Thomson parabola spectrometers.

Development of a digital star-shot analysis system for comparing radiation and imaging isocenters of proton treatment machine.

To directly compare the radiation and imaging isocenters of a proton treatment machine, we developed and evaluated a real-time radiation isocenter verification system. The system consists of a plastic scintillator (PI-200, Mitsubishi Chemical Corporation, Tokyo, Japan), an acrylic phantom, a steel ball on the detachable plate, Raspberry Pi 4 (Raspberry Pi Foundation, London, UK) with camera module, and analysis software implemented through a Python-based graphical user interface (GUI). After kV imaging alignment of the steel ball, the imaging isocenter defined as the position of the steel ball was extracted from the optical image. The proton star-shot was obtained by optical camera because the scintillator converted proton beam into visible light. Then the software computed both the minimum circle radius and the radiation isocenter position from the star-shot. And the deviation between the imaging isocenter and radiation isocenter was calculated. We compared our results with measurements obtained by Gafchromic EBT3 film (Ashland, NJ, USA). The minimum circle radii were averaged 0.29 and 0.41mm while the position deviations from the radiation isocenter to the laser marker were averaged 0.99 and 1.07mm, for our system and EBT3 film, respectively. Furthermore, the average position difference between the radiation isocenter and imaging isocenter was 0.27mm for our system. Our system reduced analysis time by 10min. Our system provided automated star-shot analysis with sufficient accuracy, and it is cost-effective alternative to conventional film-based method for radiation isocenter verification.

Science and Business Developments

Science and Business Developments

Keeping a Clean Surface under Water: Nanoscale Nipple Array Decreases Surface Adsorption and Adhesion Forces

While nanoscale nipple arrays are expected to reduce light reflection and/or dust contamination in some insects, similar structures have been reported in various marine invertebrates. To evaluate the anti-contamination property of the structure in aquatic regimes, we measured the adsorption and adhesion forces on the flat surface and MOSMITE™ (Mitsubishi Chemical Corporation, Tokyo, Japan), a synthetic material mimicking the nipple array, under water. A small force toward the surface occurred when the probe approached the substrate surface. This adsorption force was significantly smaller on MOSMITE™ than on the flat surface. The adhesion force toward the surface occurred when the probe was detached from the surface, and it was also significantly smaller on MOSMITE™ than on the flat surface. The adhesion force in the air was much greater than the force under water, and the force was also significantly smaller on MOSMITE™ than on the flat surface. In the aquatic regime, the nipple array provides less adsorption/adhesion properties for the surface and thus, the organisms would have less contamination of microparticles on their body surface. As the adsorption and adhesion forces are also involved in the attachment of cells, tissue, and larvae, less adhesive body surfaces should be beneficial for survival in aquatic environments, as well as land environments.

Corporate Philosophy for Sustainable New Product Development: A Practice of Mitsubishi Chemical Corporation

Corporate Philosophy for Sustainable New Product Development: A Practice of Mitsubishi Chemical Corporation

Mitsubishi Chemical to consolidate membrane business

Mitsubishi Chemical Corporation (MCC) is transferring the membrane-related technology development and sales currently undertaken by its subsidiary Mitsubishi Chemical Aqua Solutions Co Ltd (MCAS) to its own operations from 1 April 2021.

Development of bio-based poly(butylene succinate) formulations for microcellular injection foaming

Manufacturing lightweight plastic parts with high productivity while maintaining a high level of quality and excellent reproducibility of cellular structure reduces the amount of raw material needed while improving the carbon balance thanks to the bio-sourced origin of the polymer and the decrease of the transported mass. In this study, structural modifications of PBS were carried out in order to control the foaming mechanism in each phase of cell formation (gas dissolution, cell nucleation, cell growth and cell stabilization). Cell morphology has been improved by modifying the molecular architecture (ramified/branched, semi-reticulate structures), promoting nucleation (decrease of surface tension leading to a decrease in Gibbs’s energy barrier), or by adjusting the extensional viscosity or Newtonien viscosity of the material. The resulting formulation exhibits a decrease of more than 80% in cell size and a cell density multiplied by 450 regarding the linear structured injection moulding PBS reference FZ71 (Mitsubishi Chemical Corporation (MCC), Japan) noted here L-PBS.

Donor/Acceptor Type Polymer Semiconductor Applicable for Organic Thin-Film Transistors without Surface Modification on Printed Silver Electrodes

<Introduction> Organic thin-film transistor (OTFT) devices have attracted much attention in viewpoint of printed-electronics that realizes inexpensive, large-area and flexible devices in the near future. Mitsubishi Chemical Corporation (MCC) has investigated organic semiconductor (OSC) for more than a decade, and focuses recently on development of donor/acceptor (DA) type polymer semiconductors[1-4]. Improvement of OTFT device mobility by novel OSC materials is still one of the biggest issues in the development phase. However, their additional features that can make device fabrication process simpler are also an important industrialization standpoint in material selection. In this paper, we present DA type polymer semiconductor that enables uncomplicated device fabrication process without self-assembled monolayer (SAM) modification on printed silver electrode surface. <Experiments> Top-gate, bottom-contact devices were fabricated as follows. Silver source and drain (S/D) electrodes were patterned by ink-jet printing on Parylene underlayer on a glass substrate. After preparation of bank structure by a dispenser system using solution of amorphous fluoropolymer, semiconducting layer (MCC’s OSC; MOP-01) was printed into an area defined by the bank by a dispenser equipment using its dilute mesitylene solution. Parylene polymer dielectric (thickness: 300 nm) was then deposited on the surface under vaccum. Finally silver gate electrode was patterned by ink-jet printing on the polymer dielectric. Channel length and channel width of the devices are 30-40 μm and 1000 μm, respectively. During the fabrication process described above, three kinds of the silver S/D electrode surface were prepared with or without SAM modification. The SAM molecule introduced at the electrode surface is either pentafluorobenzenethiol (PFBT) commonly used for p-type OSC or 4-methylbenzenethiol (4MBT) normally used for n-type OSC. Silver S/D electrodes without SAM modification were also prepared for comparison. <Results and Discussion> Transfer characteristics of the fabricated OTFT were measured by semiconductor parameter analyzer. The OTFTs exhibited a field-effect mobility of 0.4 cm2/Vs with 4MBT SAM, 0.5 cm2/Vs without SAM, and 0.6 cm2/Vs with PFBT SAM in a saturation region (VDS = -10V) as an average with an on/off current ratio of about 106. The mobility difference is quite small regardless of the presence or absence of the SAM and its species. In addition, mobility among several devices was adequately uniform in each case. According to these findings, we were able to fabricate complementary organic inverter circuits successfully with fewer process steps by combining MOP-1 and n-type OSC (TU-3, Future Ink corporation) where only 4MBT was utilized as an electrode surface modifier[5]. The inverter circuit realized low power operation with excellent performance. <Acknowledgments> T.M. would like to thank all the collaborators in Mitsubishi Chemical Center for Advanced Materials (MC-CAM) in University of California, Santa Barbara (UCSB). This work was partially supported by the Japan Science and Technology Agency (JST, the center of Innovation Program). <References> L. Ying et al., J. Am. Chem. Soc., 2011, 133, 18538–18541.H.-R. Tseng et al., Adv. Mater., 2014, 26, 2993–2998.M. Wang et al., Chem. Commun., 2016, 52, 3207-3210.M. Wang et al., J. Am. Chem. Soc., 2017, 139, 17624–17631.Y. Takeda et al., the 65th JSAP Spring Meeting, 2018, 18p-D102-17.

三菱化学(株)における制御技術研究

三菱化学(株)における制御技術研究

三菱化学（株）鹿島事業所「被災から再稼働まで」

三菱化学（株）鹿島事業所「被災から再稼働まで」

Influence of Reactions of Carbon Black and Fuel Diffusion Process on Power Generation Characteristics of Rechargeable Solid Carbon Fuel Cells(RSCFCs)

INTRODUCTION Our research group proposed a Rechargeable Direct Carbon Fuel Cell (RDCFC) based on SOFCs, in which carbon is deposited in the pores of the anode by charging hydrocarbons [1]. A issue in RDCFCs is low utilization caused by low amount of deposited carbon. For higher fuel utilization, we also proposed a Rechargeable Solid Carbon Fuel Cell (RSCFC), in which solid state carbon black (CB) is directly supplied as fuel. In RSCFCs, the dominant electrochemical reaction apparently is CO oxidation reaction[2] [3] because CB is difficult supplied close to TPB (Triple Phase Boundary), and CO was generated by Boudouard corrosion reaction (C+CO2→2CO). In an earlier study, we reported that improvement in the maximum power density PMax of RSCFCs depends on the amount of CB. In RSCFCs, high power density P with high fuel utilization U is achieved at the steady state current density i0, which is reached when the CO supply rate rsup (includes the CO generation reaction rate rCO, and both CO and CO2 diffusion rates rD(CO), rD(CO 2 ) in the anode is comparable to the electrochemical reaction rate re (CO + O2- → CO2 + 2e-). The introduction of carbon black into pores made the direct carbon oxidation (C + 2O2- → CO2 + 4e-, C + O2- → CO + 2e-) enhanced and improved the power density.In this study, we (a) analyzed mass transport in CB supply column using gas diffusion theory, (b) investigated the influence of CB supply densityη(=m/SL, m is amount of CB, S is cross-section area of column, and L is the distance of CB supplied) and the rate of anode porosity εe on the power density. EXPERIMENTAL The anode of the RSCFC cell was Ni/Gd0.2Ce0.8O2 (Ni/GDC) and with added 1.85wt% CB (Ni/GDCCB) to obtain a high rate of porosity in CB column εCB (=1-(true volume of CB particle / volume of column)= 1-ηρ, hereρis true density of CB). The cathode was porous La 0.85Sr0.15MnO3, and the electrolyte was a disk of 10% Sc2O3 -1 mol% CeO2 – 89% ZrO2 (ScSZ; 20-mm diameter, 0.3-mm thick; Japan Fine Ceramics Co., Ltd.). Solid state CB was used as fuel (MA7, Mitsubishi Chemical Corporation, Mitsubishi carbon). A constant amount of CB was added into a column and the εCB was varied from 90.2% to 88.2% by changing the length of column from 6 cm to 5 cm. For power generation, a gas mixture of Ar and 5% H2 was introduced to the anode at 202STP ml/min. Power generation was started at 900°C with no gas to anode but pure O2to the cathode. Terminal Voltage V was measured.RESULTS AND DISCUSSIONFig.1 shows the performance curves of the RSCFC for different εCB. With small εCB (Fig.1b), PMax was higher. It was because of an increase in the rsup caused by the increase in the rCO due to increase in the total surface area of CB per unit volume of CB supply column.Fig.2 shows the surface SEM photograph of the Ni/GDC electrode in Fig.3 (a) and Ni/GDCCB (1.85wt %) in Fig.3 (b). We can see εeincreased by adding CB to Ni/GDC.Fig.3 shows the IV characteristics in each power generation cycle of the cell using (a) Ni/GDC electrode and (b) Ni/GDCCB (1.85wt %). In the power generation using the Ni/GDCCB (1.85wt %) electrode, which had larger εe than the Ni/GDC electrode, the maximum current density iMax was improved by 30 mA/cm2 and PMax improved by 50% (to 34.6mW/cm2). The possible reasons for the enhancement were considered as (1) an enhancement of direct oxidation of CB due to the inner surface of the anode, and (2) a reduction of pore diffusion resistor inside the anode. CONCLUSION The PMax of RSCFC with 2% less εCB of an anode was improved by 6.74 mW/cm2. It was because of an increase in the rsup caused by the increase in the rCO due to increase in the total surface area of CB per unit volume of CB supply column. Meanwhile, by using large εe of an anode, the PMax was increased (using Ni/GDC1.85%CB anode, improved by 11.72 mW/cm2). The possible reasons for the improvement were (1) an enhancement of direct oxidation of CB due to the inner surface of anode, and (2) a reduction of pore diffusion resistor inside the anode.REFERENCES1. Fuhito Ohba, Yuki Tagawa, Yu Sakai, Akinori Yabuki, Hiroyuki Shimada, and Manabu Ihara. ECS Trans. 33 (40), 163 (2011)2. Chikara Takei，Ying Chen, Manabu Ihara, ECS transactions, 33 (40), 175 (2011)3.X.-Y.Zhao, Q.Yao, S.-Q.Li, N.-S.Cai, Journal of Power Sources, 185(2008)104-111

Promoting Discussions in Safety Review Activity

Discussion from diversified viewpoints is very important for process safety review. Therefore to promote discussion is essential for improvement of process safety. Mitsubishi Chemical Corporation has been working to improve process safety by performing safety review (SR) activities. The aim of the SR activity is to improve safety of processes and operations by sharing information from a broad range of perspectives. The SR activities are joined not only by staffs who are familiar with routine operation, but also by staffs who belong to other departments. To strengthen the SR activity, SR Instructor Team was formed. The member of SR instructor team is composed of retired and senior engineers who have abundant knowledge and experience about processes and safety measures. The SR activity becomes a field where experiences, perspectives and knowledge are shared by participants. To facilitate the SR activity, HAZchart analysis is used for risk evaluation method. It facilitates process of risk evaluation from accident scenario formulation to quantitative evaluation and enables worst-case scenarios to be easily assumed. By using HAZchart analysis supporting software that is called PHA_Organizer, anyone has been able to conduct risk evaluation easily. This software was privately used at first. But it became clear that PHA_Organizer could facilitate sharing a mutual thinking process and promote discussion at a meeting. Consequently PHA_Organizer was significantly improved to make the tool even easier to use and anyone could easily conduct risk evaluations at a meeting. The main improved points are common cause specific function, minimal cut set display function and redundant system drawing function and improvement of user interface, etc. Promoting discussions in Safety Review Activity is expected by these upgrades.

Selective separation of Cr(III) and Fe(III) from liquid effluents using a chelating resin

This study aimed to assess the selective separation of Cr(III) from Fe(III) from liquid solutions by using a chelating ion exchange resin, Diaion CR 11, from Mitsubishi Chemical Corporation, in the H(+) form. Equilibrium experiments with synthetic solutions of iron and chromium were carried out in batch mode. For both metals favorable adsorption isotherms were obtained, and the experimental data were well described by the Langmuir model. However, the resin exhibited higher affinity for iron than for chromium. The regeneration experiments revealed that, for both metals, HCl provided higher removal efficiencies than H(2)SO(4) and HNO(3). Moreover, precipitation with NaOH allows selectively separate chromium and iron to be stripped from the resin. Experiments in fixed bed operation were carried out to assess the dynamic behavior of the sorption of Cr(III) and Fe(III) into the tested resin by using synthetic and industrial solutions. The experiments with industrial effluent showed that the resin can remove low levels of contaminant transition metal ions, and thus the effluent can be purified for reuse of chromium during periods of 20-25 min. The resin regeneration was achieved with a sequential treatment with HCl and NaOH/H(2)O(2). High efficiencies were observed for both monocomponent and multicomponent systems. A global strategy for separating and recovering Cr(III) from an effluent that also contains Fe(III) is presented, involving the integration of ion exchange (saturation and regeneration phases) and precipitation processes. In conclusion, our approach demonstrates that efficient separation of chromium and iron is possible if ion exchange operation in a fixed bed configuration is optimized and combined with conventional processes such as precipitation.

職場における化学物質管理の今後のあり方をめぐって

1 National Institute of Occupational Safety and Health, Japan 2 Department of Medical Care and Welfare Engineering, Graduate School of Science and Technology, Nihon University, Japan 3 Chemical Hazards Control Division, Industrial Safety and Health Department, Labor Standards Bureau, Ministry of Health, Labor and Welfare, Japan 4 Environment, Safety and Quality Department, Mitsubishi Chemical Corporation, Japan 5 Medicine and Occupational Health, EMG Marketing Godo Kaisya, Japan 6 School of Creative Science & Engineering, Waseda University, Japan

Development of Highly Selective Process for Mono-Ethylene Glycol Production from Ethylene Oxide via Ethylene Carbonate Using Phosphonium Salt Catalyst

A new process for the production of mono-ethylene glycol (MEG; HOCH2CH2OH) was developed by Mitsubishi Chemical Corporation (MCC) to meet its growing demand in the world. While the MEG selectivity of conventional non-catalyzed process is around 89% under typical conditions, that of the new process exceeds 99%. The key of the high selectivity is the two-step synthesis via ethylene carbonate. The first step reaction is catalyzed by phosphonium salts and generates ethylene carbonate as an intermediate. This is followed by hydrolysis of ethylene carbonate in the second step. Several commercial plants of the new process have already been operated world-wide.

Synthesis of NH006—a photostable fungicide effective against Botrytis cinerea—according to the asymmetric total synthesis of MK8383

MK8383, isolated from Phoma sp. T2526 in 1993, exhibits potent antibiotic activities against a variety of phytopathogens and has been considered a promising fungicide against Botrytis cinerea. Unfortunately, MK8383 is a photosensitive compound and it undergoes irreversible decomposition. Although much effort has been devoted to improving the photostability of MK8383 by chemical modification of its structure by a research group organized by Meiji Seika Kaishya, Ltd. and Mitsubishi Chemical Corporation, a photostable MK8383 derivative has never been prepared. We have found that a C13-14 double bond of MK8383 and (+)-phomopsidin is responsible for the photosensitivity, and herein, we report the synthesis of NH006, an MK8383 derivative with a saturated C13-14 double bond and (S) configuration at C14, based on the asymmetric total synthesis of MK8383. NH006 exhibits good photostability and potent antifungal activity against B. cinerea.

Field‐theoretic simulations of polyelectrolyte complexation

Field‐theoretic simulations of polyelectrolyte complexation

Interfacial adsorption of lipases on very hydrophobic support (octadecyl–Sepabeads): immobilization, hyperactivation and stabilization of the open form of lipases

Octadecyl–Sepabeads (Mitsubishi Chemical Corporation) was used to immobilize the lipases from Candida antarctica (fraction B), from Mucor miehei and from Candida rugosa via interfacial adsorption. The activity and stability properties of the derivatives obtained using this strategy by “stabilization of the open structure of the lipase” were compared to other more conventional immobilized derivatives (e.g. those obtained by multipoint covalent attachment) where the lipases are likely to be immobilized exhibiting its closed structure. Lipases adsorbed on hydrophobic supports exhibited a clear hyper-activation compared to the soluble enzyme or other types of derivatives. Their specific activities were greatly improved after immobilization (M. miehei lipase derivative was even 20 times more active than the soluble enzyme). Furthermore, lipases adsorbed on hydrophobic supports were very stable against heat and organic solvents inactivation. For example, C. antarctica B lipase octadecyl derivatives preserved 100% of the activity after 200h of incubation at pH 7 and 50°C. In addition, these derivatives remained also fully active after a very long incubation (200h) in 50% dioxane at pH 7 and 25°C. In spite of being immobilized by simple physical adsorption these lipase derivatives were more stable than multipoint covalently immobilized derivatives and much more stable than their respective soluble enzyme. It seems that the “open structure” of lipases, adsorbed on hydrophobic supports, is much more active and much more stable than the corresponding “closed” structure even when the closed structure is undergoing a very intense multipoint covalent attachment.

A Preparation Method of Thermoreversible Poly(vinyl chloride) Gels

ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTA Preparation Method of Thermoreversible Poly(vinyl chloride) GelsYuji AokiView Author Information Chemical Science Laboratories, Mitsubishi Chemical Corporation, 1, Toho-cho, Yokkaichi, Mie 510-8530, Japan Cite this: Macromolecules 2001, 34, 10, 3500–3502Publication Date (Web):April 6, 2001Publication History Received27 November 2000Revised21 February 2001Published online6 April 2001Published inissue 1 May 2001https://doi.org/10.1021/ma002011iCopyright © 2001 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views223Altmetric-Citations16LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (72 KB) Get e-AlertsSUBJECTS:Equilibrium,Evaporation,Physiology,Quenching,Viscoelasticity Get e-Alerts

除草剤インダノファンの創製

Indanofan ((RS) -2-[[2-(3-chlorophenyl) oxiranyl] methyl] -3-eth ylindan-1, 3-dione), a novel class of grass herbicide, was discovered by Mitsubishi Chemical Corporation during the study of oxiran containing herbicidally active compounds. It was introduced into the market in 1999, and is now widely used as the active ingredient for One-shot rice herbicides in Japan. It controls Echinochloa oryzicola of 0 to 2.5 leaf-stage at 100 to 150g a.i./ha for enough periods even at low temperature.Indanofan is characterized by its unique chemical structure due to indan-1, 3-dione and 2-phenyl substituted oxirane moieties bridged via methylene carbon atom. This paper describes firstly the drug design process for indanofan, lead generation and lead optimization, and secondly the synthesis and manufacturing process of indanofan and its key intermediates, 2-ethylindan-1, 3-dione and 1-chloro-3- (1-chloromethylvinyl) benzene including the oxidation process using high concentration peracetic acid.