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Cellulose mixed esters (CMEs) substituted with two different types of acyl groups are promising polymeric materials with various tunable properties but are arduous to produce. This is because of the insolubility of cellulose in common solvents, and thus, the industrial production of CMEs with desired degrees of substitution (DSs) requires a costly multistep process. To accomplish their facile production, homogeneous reactions have been performed using ionic liquids (ILs) as solvents for cellulose. However, the high viscosity of the cellulose-IL solutions causes insufficient mixing in batch reactors; thereby, favoring low cellulose concentrations with long reaction times (typically hours). Herein, we demonstrate a rapid and scalable production of CMEs by exploiting the excellent shear mixing of a twin-screw extruder as a flow reactor. A co-solvent system comprising an IL, 1-ethyl-3-methylimidazolium acetate, and dimethyl sulfoxide was applied to dissolve cellulose at a high concentration (15 wt.%) via twin-screw extrusion. During continuous extrusion at 80 degrees C, cellulose reacted with two acyl reagents, isopropenyl acetate (IPAc) and vinyl propionate (VPr) (2.5:0.5, mol/mol), to yield cellulose acetate propionate (CAP) within minutes. The CAP was stably produced during the operation time of 50 min with an average isolated yield of 71%. The DSs of the acetyl and propionyl groups of CAP were 1.77 and 0.50, respectively, corresponding to sufficiently high conversion rates of 70% for IPAc and 100% for VPr.

Cellulose mixed esters (CMEs) substituted with two different types of acyl groups are promising polymeric materials with various tunable properties but are arduous to produce. This is because of the insolubility of cellulose in common solvents, and thus, the industrial production of CMEs with desired degrees of substitution (DSs) requires a costly multistep process. To accomplish their facile production, homogeneous reactions have been performed using ionic liquids (ILs) as solvents for cellulose. However, the high viscosity of the cellulose-IL solutions causes insufficient mixing in batch reactors; thereby, favoring low cellulose concentrations with long reaction times (typically hours). Herein, we demonstrate a rapid and scalable production of CMEs by exploiting the excellent shear mixing of a twin-screw extruder as a flow reactor. A co-solvent system comprising an IL, 1-ethyl-3-methylimidazolium acetate, and dimethyl sulfoxide was applied to dissolve cellulose at a high concentration (15 wt.%) via twin-screw extrusion. During continuous extrusion at 80 degrees C, cellulose reacted with two acyl reagents, isopropenyl acetate (IPAc) and vinyl propionate (VPr) (2.5:0.5, mol/mol), to yield cellulose acetate propionate (CAP) within minutes. The CAP was stably produced during the operation time of 50 min with an average isolated yield of 71%. The DSs of the acetyl and propionyl groups of CAP were 1.77 and 0.50, respectively, corresponding to sufficiently high conversion rates of 70% for IPAc and 100% for VPr.

Cellulose mixed esters (CMEs) substituted with two different types of acyl groups are promising polymeric materials with various tunable properties but are arduous to produce. This is because of the insolubility of cellulose in common solvents, and thus, the industrial production of CMEs with desired degrees of substitution (DSs) requires a costly multistep process. To accomplish their facile production, homogeneous reactions have been performed using ionic liquids (ILs) as solvents for cellulose. However, the high viscosity of the cellulose-IL solutions causes insufficient mixing in batch reactors; thereby, favoring low cellulose concentrations with long reaction times (typically hours). Herein, we demonstrate a rapid and scalable production of CMEs by exploiting the excellent shear mixing of a twin-screw extruder as a flow reactor. A co-solvent system comprising an IL, 1-ethyl-3-methylimidazolium acetate, and dimethyl sulfoxide was applied to dissolve cellulose at a high concentration (15 wt.%) via twin-screw extrusion. During continuous extrusion at 80 degrees C, cellulose reacted with two acyl reagents, isopropenyl acetate (IPAc) and vinyl propionate (VPr) (2.5:0.5, mol/mol), to yield cellulose acetate propionate (CAP) within minutes. The CAP was stably produced during the operation time of 50 min with an average isolated yield of 71%. The DSs of the acetyl and propionyl groups of CAP were 1.77 and 0.50, respectively, corresponding to sufficiently high conversion rates of 70% for IPAc and 100% for VPr.

Thermoplastic elastomers (TPEs) have long been used in a wide range of industries. However, most existing TPEs are petroleum-derived polymers. To realize environmentally benign alternatives to conventional TPEs, cellulose acetate is a promising TPE hard segment because of its sufficient mechanical properties, availability from renewable sources, and biodegradability in natural environments. Because the degree of substitution (DS) of cellulose acetate governs a range of physical properties, it is a useful parameter for designing novel cellulose acetate-based TPEs. In this study, we synthesized cellulose acetate-based ABA-type triblock copolymers (AcCelx- b-PDL-b-AcCelx) containing a celloologosaccharide acetate hard A segment (AcCelx, where x is the DS; x = 3.0, 2.6, and 2.3) and a poly(o-decanolactone) (PDL) soft B segment. Small-angle X-ray scattering showed that decreasing the DS of AcCelx-b-PDL-b-AcCelx resulted in the formation of a more ordered microphase-separated structure. Owing to the microphase separation of the hard cellulosic and soft PDL segments, all the AcCelx-b- PDL-b-AcCelx samples exhibited elastomer-like properties. Moreover, the decrease in DS improved toughness and suppressed stress relaxation. Furthermore, preliminary biodegradation tests in an aqueous environment revealed that the decrease in DS endowed AcCelx-b-PDL-b-AcCelx with greater biodegradability potential. This work demonstrates the usefulness of cellulose acetate-based TPEs as next-generation sustainable materials.

source:https://www.nms.ac.jp/sh/jnms/2021/088040335.pdf

Adversarial Internet robots (botnets) represent a growing threat to the safe use and stability of the Internet. Botnets can play a role in launching adversary reconnaissance (scanning and phishing), influence operations (upvoting), and financing operations (ransomware, market manipulation, denial of service, spamming, and ad click fraud) while obfuscating tailored tactical operations. Reducing the presence of botnets on the Internet, with the aspirational target of zero, is a powerful vision for galvanizing policy action. Setting a global goal, encouraging international cooperation, creating incentives for improving networks, and supporting entities for botnet takedowns are among several policies that could advance this goal. These policies raise significant questions regarding proper authorities/access that cannot be answered in the abstract. Systems analysis has been widely used in other domains to achieve sufficient detail to enable these questions to be dealt with in concrete terms. Defeating botnets using an observe-pursue-counter architecture is analyzed, the technical feasibility is affirmed, and the authorities/access questions are significantly narrowed. Recommended next steps include: supporting the international botnet takedown community, expanding network observatories, enhancing the underlying network science at scale, conducting detailed systems analysis, and developing appropriate policy frameworks., Comment: 26 pages, 13 figures, 2 tables, 72 references, submitted to PlosOne

高速増殖原型炉もんじゅでは、現在、廃止措置が進められており、その第一段階として、炉心に装荷している燃料を取り出す工程がある。炉心の燃料集合体は、エントランスノズルが炉心支持板の連結管に挿入され自立しており、周辺の集合体によりパッド部を介して支え合い炉心体系を維持する構造となっている。そのため、燃料を取り出した場所に模擬燃料集合体を装荷し、燃料集合体を安定させる必要があった。このような背景を受け、もんじゅ炉心燃料集合体の製造経験のあるプルトニウム燃料技術開発センターへ、もんじゅ側から模擬燃料集合体の製造依頼があり、製造を行った。この報告書は、装荷する模擬燃料集合体の設計、製造、出荷について報告するものである。, The decommissioning is currently in progress at the prototype fast breeder reactor Monju. Fuel assemblies will be taken out of its core for the first step of the great task. Fuel assemblies stand on their own spike plugged into a socket on the core support plate and support with adjacent assemblies through their housing pads each other, resulting in steady core structure. For this reason, some substitutive assemblies are necessary for the purpose of discharging the fuel assemblies of the core. Monju side commissioned, therefore, Plutonium Fuel Development Center to manufacture the substitutive assemblies and the Center accepted it. This report gives descriptions of design, manufacture, and shipment in regard to the substitutive assemblies., 著者所属: 日本原子力研究開発機構(JAEA), JAEA-Technology 2020-020

Anugītā は古代インド叙事詩Mahābhārata に収められている四つの主要な哲学編の一つであり、他の哲学編同様、古典期のサーンキヤ・ヨーガ哲学以前の、初期サーンキヤ・ヨーガ哲学の諸説を断片的に残している。しかしその思想史的重要性にもかかわらず、AG は古代インドの伝統においても西洋的インド学の研究においても、Mahābhārata において最も有名な哲学編であるBhagavadgītāの補遺あるいは模倣にすぎないと見做され、いくつかの重要な例外を除いてこれまで活発に研究されることはなかった。本論文ではAnugītā 15 に見られるアラルカ王のヨーガについての逸話を取り上げ、心(manas) はどのようなものとして捉えられ、ヨーガの修行において心はどのような役割を担うと考えられているのかを明らかにする。 大地を征服したアラルカ王は、心を集中させて(manas + sam + ā + √dhā) 、思索(cintā) を巡らし、自分自身の七人のホータル祭官たち（心[manas] と五つの感覚機能たちと知性[buddhi]）を自らの敵と考え、矢たちを放って殺そうとする。しかし七人のホータル祭官たちは、そのようなことをしても自分たちを殺すことはできず、逆にアラルカ王自身を殺してしまうことになるとして、アラルカ王を思いとどまらせる。次に彼は苦行を行って至福に達しようとするが、これも失敗に終わる。最後に彼は心を一点集中させ（ekāgraṃ manaḥ + √kar）長い時間思索を巡らし（[vi] + √cint）、ヨーガという一本の矢によって七人のホータル祭官のうち五つの感覚機能たちを速やかに殺し、ヨーガこそが至福に到達する道であると理解する。 アラルカ王の第一の試みにおいて見られた心の集中と思索は、ヨーガにおいてさらに深化・強化されて受け継がれている一方、第一の試みにおいては心は七人のホータル祭官たちの力の源として真っ先に殺されるべき対象と捉えられているのに対して、ヨーガにおいては心を一点集中状態に導くことで心から生じる力を得て、速やかに感覚機能たちを殺すことを可能にしてくれるものとして捉えられていることに大きな違いがある。また興味深いことに、知性はアラルカ王の第一の試みの記述においては言及されるが、ヨーガの叙述においては言及されていない。初期ヨーガ哲学では、精神原理として知性や自我意識について説いていても解脱道においては心が中心的な役割を果たすことが多く、アラルカ王の説話もその一つと言えるだろう。, 広島大学比較論理学プロジェクト研究センター研究成果報告書（2017年度）, This work was supported by JSPS KAKENHI Grant Numbers 15J07295.

Context: It is important to develop a method to accurately measure controlled force exertion (CFE). Objectives: This study aimed to examine the effect of maximum grip strength on CFE measured by a sinusoidal waveform in 81 right-handed young males aged 15-29years. Methods: On the basis of grip strength measurements, participants were divided into the following three groups: low (males 20; mean age 19.5years; standard deviation (SD)=5.0years), medium (males 41; mean age 22.8years; SD=4.2years), and high (males 20; mean age 23.7years; SD=3.4years). Participants adjusted the submaximal grip strength of the dominant hand with changes in the demand values that were displayed as a sinusoidal waveform with a frequency of 0.1Hz on a computer screen. The abovementioned test was performed three times with a 1-min interval after one practice trial. Each trial lasted 40s. The sum of the differences between the demand value and grip exertion strength value for 25s was considered as the evaluation parameter. Results: Controlled force exertion values demonstrated insignificant correlations with age and maximum grip strength in all groups (r=0.07; r=-0.12; p>0.05). No significant differences were found between CFE mean scores that was adjusted for age and varying maximum grip strength in the three groups (F=1.95; p>0.05). Conclusions: Based on the sinusoidal waveform display, we inferred that maximum grip strength has little effect on CFE evaluation in young males. © 2014 Springer-Verlag Italia.

Polyorganosilsesquioxanes (RSiO3/2) (R: organic group) particles with different organic groups such as alkyl and aryl groups were prepared using a two-step acid–base catalyzed sol–gel process. Spherical particles were formed at room temperature using the two-step acid–base catalyzed sol–gel process in which trifunctional organoalkoxysilanes with R = methyl, n-propyl, n-butyl, phenyl, and benzyl were used as starting materials. Polyorganosilsesquioxanes with longer alkyl groups or phenethyl group prepared by the two-step acid–base catalyzed sol–gel process were oily material at room temperature. Polyorganosilsesquioxanes with shorter alkyl or aryl groups exhibited the glass transition. In contrast, polyorganosilsesquioxanes with longer alkyl groups showed no glass transition behavior. The occurrence of glass transition phenomena of polyorganosilsesquioxanes was concluded to be strongly dependent on the chain length of organic substituents.

減容処理棟に設置されている金属溶融設備は、原子力科学研究所に保管廃棄された低レベル放射性廃棄物のうち、金属廃棄物について溶融し、溶融固化体とすることにより、放射性廃棄物の減容,安定化を図るものである。これまでの試験運転結果を踏まえて、本設備のうち、溶融した金属から金属塊(インゴット)を作製する成型工程の改善工事を実施した。また、平成20年10月から試験運転を実施し、合理化した成型工程の検証を行った。本稿では、試験運転によって得られた合理化した成型工程での処理時間の短縮効果,ユーティリティ消費量の低減効果,保守作業の負担軽減効果等について報告する。, The Waste Volume Reduction Facility (WVRF) was constructed for volume reduction and the chemical stabilization of the low level radioactive waste in the Nuclear Science Research Institute of JAEA. The metal melting system in the WVRF treats radioactive metal waste. From the experience of trial operations, the improvement has conducted on the casting process in the metal melting system. The performance of the improved casting process was verified through the trial operations from Oct. 2008. In this report, we describe the reduction of the processing time, of the utilities consumption, of the load of maintenance on the improved casting process., 著者所属: 日本原子力研究開発機構(JAEA), JAEA-Technology 2010-008

減容処理棟に設置されている金属溶融設備は、原子力科学研究所に保管廃棄された低レベル放射性廃棄物のうち、金属廃棄物について溶融し溶融固化体とすることにより、放射性廃棄物の減容,安定化を図る。本設備は、平成15年度から試験運転を実施しており、その試験運転の経験から、溶融した金属の成型工程において、処理コストの低減,保守作業の負担軽減,保守作業に伴う作業員の被ばくの低減等に向けた知見が得られた。その知見を具体化するための設計検討,改善工事を平成18年度から19年度に実施し、成型工程の合理化のための設備改善が実現した。本稿では、金属溶融設備での成型工程の合理化のための検討,設備改善内容,評価等について報告する。, The Waste Volume Reduction Facility (WVRF) was constructed for volume reduction and the chemical stabilization of the low level radioactive waste (LLW). The metal melting system in the WVRF treats radioactive metal waste. This system has been conducted commissioning since the FY 2003. It was found, from the experience of commissioning, that the improvement of casting process in the metal melting system can be reduced the processing cost, maintenance load, and dose to workers. We planed modification of the device, and embodied from FY 2006 to FY 2007. As a result, we properly improved the casting process. In this report, we describe the idea for improvement of the casting process, the detail of improvement and the estimate of improvement., 著者所属: 日本原子力研究開発機構(JAEA), JAEA-Technology 2009-031

高減容処理施設は、放射性廃棄物の廃棄体を作製する目的で日本原子力研究開発機構原子力科学研究所(旧日本原子力研究所東海研究所)に建設された施設である。施設は、大型金属廃棄物の解体・分別及び廃棄体等の保管廃棄を行う解体分別保管棟と溶融処理等の減容・安定化処理を行って廃棄体を作製する減容処理棟からなる。減容処理棟には、金属溶融炉,プラズマ溶融炉,焼却炉,高圧圧縮装置といった減容・安定化処理を行うための設備が設置されている。本報告では、施設建設の基本方針,施設の構成,各設備の機器仕様と2006年3月までに行った試運転の状況などについてまとめた。, The Advanced Volume Reduction Facilities (AVRF) is constructed to manufacture the waste packages of radioactive waste for disposal in the Nuclear Science Research Institute of the Japan Atomic Energy Agency. The AVRF is constituted from two facilities. The one is the Waste Size Reduction and Storage Facility (WSRSF) which is for reducing waste size, sorting into each material and storing the waste package. The other is the Waste Volume Reduction Facility (WVRF) which is for manufacturing the waste package by volume reducing treatment and stabilizing treatment. WVRF has an induction melting furnace, a plasma melting furnace, an incinerator, and a super compactor for treatment. In this report, we summarized about the basic concept of constructing AVRF, the constitution of facilities, the specifications of machineries and the state of trial operation until March of 2006., 著者所属: 日本原子力研究開発機構(JAEA), JAEA-Technology 2007-038

The synthesis of a novel unimolecular reverse micelle, the hyperbranched d-glucan carbamate (3), was accomplished through the carbamation reaction of the hyperbranched d-glucan (1) with the N-carbonyl l-leucine ethyl ester (2) in pyridine at 100 °C. Polymer 3 was soluble in a large variety of organic solvents, such as methanol, acetone, chloroform, and ethyl acetate, and insoluble in water, which remarkably differed from the solubility of 1. The degree of carbamate substitution (DS) for 3 was controlled by the feed rate of 2, and the DS values were in the range of 46.0–93.7%. Polymer 3 possessed the encapsulation ability for water-soluble molecules, such as rose bengal, thymol blue, and alizarin yellow in chloroform, and the encapsulation ability depended on the hydrophilicity of 3 and the molecular size of the dye. The rose bengal (RB) encapsulated polymer (RB/3) showed a slow release from the RB/3 system into water at neutral pH, while the release rate was significantly accelerated by the hydrolysis of the hydrophobic polymer shell under basic conditions.

Hyperbranched polythreitol (1) with different molecular weights (Mw,SLS: 1.18 × 10 4 and 4.79 × 10 4) was reacted with trityl chloride in DMF to afford a novel amphiphilic polymer (2) consisting of 1 as the hydrophilic core and the trityl groups as the hydrophobic shell. Compound 2 was tested for its ability to act as a unimolecular nanocapsule toward the water-soluble dye, rose bengal (RB). Their encapsulation and release properties were also evaluated by comparison with the degree of substitution (DS) of the trityl groups, i.e., the hydrophobic shell density. The polymers were found to have very good unimolecular nanocapsule characteristics even at extremely low concentrations. The average number of RBs per polymer molecule depended on the hydrophilic core size and the hydrophobic shell density. The increasing DS value led to a decrease in the encapsulated amount due to the decrease in the hydrophilic core space, while the low DS value (less than ca. 20 mol%) led to a destabilization as a unimolecular nanocapsule and a lower encapsulation ability. In particular, 2 with ca. 23% DS value showed an efficient encapsulation. Based on a release test of the RB-loaded unimolecular nanocapsules, the polymers showed a high RB-holding ability in water.

Spherical polyphenylsilsesquioxane particles were prepared by a two-step acid-base catalyzed sol-gel process, in which various amounts of ethanol were used as a solvent to vary the concentration of phenyltriethoxysilane (PhSi(OEt)3) used as a starting alkoxide. The decrease in the PhSi(OEt)3 concentration led to the decrease in the average molecular weight and glass transition temperature of the polyphenylsilsesquioxanes. Thus, the change of the PhSi(OEt)3 concentration in the preparation of polyphenylsilsesquioxane particles by the two-step acid-base catalyzed sol-gel process is an effective means to control the glass transition temperature of the particles.

Hyperbranched polythreitol (1) with different molecular weights (Mw,SLS: 1.18 × 10 4 and 4.79 × 10 4) was reacted with trityl chloride in DMF to afford a novel amphiphilic polymer (2) consisting of 1 as the hydrophilic core and the trityl groups as the hydrophobic shell. Compound 2 was tested for its ability to act as a unimolecular nanocapsule toward the water-soluble dye, rose bengal (RB). Their encapsulation and release properties were also evaluated by comparison with the degree of substitution (DS) of the trityl groups, i.e., the hydrophobic shell density. The polymers were found to have very good unimolecular nanocapsule characteristics even at extremely low concentrations. The average number of RBs per polymer molecule depended on the hydrophilic core size and the hydrophobic shell density. The increasing DS value led to a decrease in the encapsulated amount due to the decrease in the hydrophilic core space, while the low DS value (less than ca. 20 mol%) led to a destabilization as a unimolecular nanocapsule and a lower encapsulation ability. In particular, 2 with ca. 23% DS value showed an efficient encapsulation. Based on a release test of the RB-loaded unimolecular nanocapsules, the polymers showed a high RB-holding ability in water.

The synthesis of a novel unimolecular reverse micelle, the hyperbranched d-glucan carbamate (3), was accomplished through the carbamation reaction of the hyperbranched d-glucan (1) with the N-carbonyl l-leucine ethyl ester (2) in pyridine at 100 °C. Polymer 3 was soluble in a large variety of organic solvents, such as methanol, acetone, chloroform, and ethyl acetate, and insoluble in water, which remarkably differed from the solubility of 1. The degree of carbamate substitution (DS) for 3 was controlled by the feed rate of 2, and the DS values were in the range of 46.0–93.7%. Polymer 3 possessed the encapsulation ability for water-soluble molecules, such as rose bengal, thymol blue, and alizarin yellow in chloroform, and the encapsulation ability depended on the hydrophilicity of 3 and the molecular size of the dye. The rose bengal (RB) encapsulated polymer (RB/3) showed a slow release from the RB/3 system into water at neutral pH, while the release rate was significantly accelerated by the hydrolysis of the hydrophobic polymer shell under basic conditions.