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Torsion in the Cohomology of Torus Orbifolds

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1247-1268页

作者： Hideya kuwata Mikiya MASUDA Haozhi ZENG Department of Mathematics Osaka City UniversitySumiyoshi-kuOsaka 558-8585Japan School ofMathematical Sciences Fudan UniversityShanghai 200433China.

The authors study torsion in the integral cohomology of a certain family of2 n-dimensional orbifolds X with actions of the n-dimensional compact torus. Compact simplicial toric varieties are in our family. For a prime number p, the authors find a necessary condition for the integral cohomology of X to have no p-torsion. Then it is proved that the necessary condition is sufficient in some cases. The authors also give an example of X which shows that the necessary condition is not sufficient in general.

关键词： Toric orbifold Cohomology Torsion

Efficient high harmonics generation by enhancement cavity driven with a post-compressed FCPA laser at 10 MHz

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High Power Laser Science and Engineering 2018年第2期6卷 45-50页

作者： Zhigang Zhao Akira Ozawa Makoto kuwata-Gonokami Yohei Kobayashi The Institute for Solid State Physics The University of Tokyo Department of Physics Graduate School of Science The University of Tokyo

Efficient high harmonics generation(HHG) was demonstrated at 10 MHz repetition rate with an external femtosecond enhancement cavity, seeded by a ～70 fs post-compressed 10 MHz fiber chirped pulse amplifier(FCPA) laser. Operation lasting over 30 min with 0.1 m W outcoupled power at 149 nm was demonstrated. It was found that shorter pulse was beneficial for alleviating the nonlinear plasma effect and improving the efficiency of HHG. Low finesse cavity can relax the plasma nonlinearity clamped intra-cavity power and improve the cavity-locking stability. The pulse duration is expected to be below 100 fs for both 1040 nm and 149 nm outputs, making it ideal for applications such as time-resolved photoemission spectroscopy.

关键词： enhancement cavity high harmonics generation ultrafast fiber lasers

Experimental Evaluation of the Heat Output/Input and Coefficient of Performance Characteristics of a Chemical Heat Pump in the Periodic Operation of CaCl2Hydration

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Journal of Materials Science and Chemical Engineering 2020年第11期8卷 33-42页

作者： Atsuhiro Ichinose Kazuki kuwata Takehiro Esaki Takayuki Matsuda noriyuki Kobayashi Nagoya University Furo-cho Chikusa-ku Nagoya Aichi Japan

We herein evaluate the use of a chemical heat pump (CHP) for upgrading waste heat. CaCl2 was used in the system of CHP. We evaluated the heat storage and heat releasing of CHP, and confirmed the practicality from the experimental results. The reactor module employed was an aluminum plate-tube heat exchanger with corrugated fins, and the CaCl2 powder was in the form of a packed bed. Heat storage operation and heat dissipation operation are performed at the same time and supplied to the heat demand destination. At this time, an environmental heat source can be used during the heat radiation operation, and the heat output can release more heat than the heat input during heat storage. The heat discharging and charging characteristics of the reactor module were evaluated experimentally. The coefficient of performance (COP) was calculated for the heat upgrading cycle, and the heat output in the system was determined. A COP of 1.42 and output of 650 W/L, based on the heat exchanger volume, were obtained using a 600 s change time for the heat pump.

关键词： Chemical Heat Pump CaCl2/H2O Hydration Reaction Heat Pump Cycle Coefficient of Performance

Chemical Heat Storage Using an SiC Honeycomb Packed with CaCl2Powder

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Journal of Materials Science and Chemical Engineering 2020年第11期8卷 23-32页

作者： Atsuhiro Ichinose Kazuki kuwata Takehiro Esaki Takayuki Matsuda noriyuki Kobayashi Nagoya University Furo-cho Chikusa-ku Nagoya Aichi Japan

Chemical heat storage is a promising technology for improving thermal energy efficiency. In this study, CaCl2 and H2O were selected as a reaction system for utilization of low-grade exhaust heat that is cooler than 200°C. Heat discharging and charging were conducted through the CaCl2 hydration reaction. A silicon carbide honeycomb was adopted to improve heat transfer in the CaCl2 packed bed. The heat storage, condenser, and evaporator temperature were set at 150°C, 30°C and 90°C respectively. Repeated trials and experiments are time consuming for optimizing design of the equipment. Therefore, in this research, we constructed a simulation that can predict the performance of the device. A numerical simulation model was utilized in preparation for the design of the heat storage module. The consistency of both the simulation and the experimental results was confirmed by comparing them.

关键词： Chemical Heat Storage CaCl2 Heat Discharging Simulation

Thermochemical Heat Storage Performance in the Gas/Liquid-Solid Reactions of SrCl₂ with NH₃

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Natural Resources 2016年第11期7卷 655-665页

作者： Kazuki kuwata Soichirou Masuda noriyuki Kobayashi Takuya Fuse Toru Okamura Department of Chemical Engineering Nagoya University Nagoya Japan Denso Corporation Kariya Japan

Thermochemical heat storage is a promising technology for improving energy efficiency through the utilization of low-grade waste heat. The formation of a SrCl2 ammine complex was selected as the reaction system for the purpose of this study. Discharge characteristics were evaluated in a packed bed reactor for both the gas-solid reaction and the liquid-solid reaction. The average power of the gas-solid reaction was influenced by the pressure of the supplied ammonia gas, with greater powers being recorded at higher ammonia pressure. For the liquid-solid reaction, the obtained average power was comparable to that obtained for the gas-solid reaction at 0.2 MPa. Moreover, the lower heat transfer resistance in the reactor was observed, which was likely caused by the presence of liquid ammonia in the system. Finally, the short-term durability of the liquid-solid reaction system was demonstrated over 10 stable charge/discharge cycles.

关键词： Thermochemical Heat Storage SrCl2 Ammine Complex Formation Gas/Liquid-Solid Reaction

Formation and Decay of Electron-Hole Plasma Clusters in a Direct-Gap Semiconductor CuCl

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Chinese Physics Letters 2003年第10期20卷 1833-1835页

作者：姜磊吴明卫 M.Nagai M.kuwata-Gonokami StructureResearchLaboratory UniversityofScienceandTechnologyofChinaHefei230026 DepartmentofPhysics UniversityofScienceandTeclmologyofChinaHefe230026 DepartmentofPhysics KyotoUniversityKyoto606-8502Japan DepartmentofAppliedPhysics UniversityofTokyoHongoBunkyo-kuTokyo113-8656Japan

The master equation for the cluster-size distribution function is solved numerically to investigate the electron-hole droplet formation claimed to be discovered in the direct-gap CuCl excited by picosecond laser pulses [Nagai et al. Phys. Rev. Lett. 86 (2001) 5795; J. Lumin. 100 (2002) 233]. Our result shows that for the excitation in the experiment, the average number of pairs per cluster (ANPC) is only around 5.2, much smaller than that (10~6 typically for Ge) of the well studied electron-hole droplet in indirect-gap semiconductors such as Ge and Si. These results indicate that what measured in CuCl by Nagai et al. may not come from the EHD formed from exciton gas, instead possibly come from some bubbles of excitons in metallic liquid.

关键词： Exciton Electrohydrodynamics bubbles Semiconductor materials decay lumin Excitation Clusters Distribution function aluminium Decay Electron-hole plasma Master equation Picosecond pulsed laser device digitally

Exploration of organic superionic glassy conductors by process and materials informatics with lossless graph database

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npj Computational Materials 2022年第1期8卷 1622-1629页

作者： Kan Hatakeyama-Sato Momoka Umeki Hiroki Adachi Naoaki kuwata Gen Hasegawa Kenichi Oyaizu Department of Applied Chemistry Waseda University3-4-1 OkuboShinjukuTokyo169-8555Japan National Institute for Materials Science(NIMS) 1-1 NamikiTsukuba305-0044Japan

Data-driven material exploration is a ground-breaking research style;however,daily experimental results are difficult to record,analyze,and *** report a data platform that losslessly describes the relationships of structures,properties,and processes as graphs in electronic laboratory *** a model project,organic superionic glassy conductors were explored by recording over 500 different *** data analysis revealed the essential factors for a remarkable room temperature ionic conductivity of 10^(−4)–10^(−3) S cm^(−1) and a Li^(+) transference number of around *** contrast to previous materials research,everyone can access all the experimental results,including graphs,raw measurement data,and data processing systems,at a public *** data sharing will improve scientific communication and accelerate integration of material knowledge.

关键词： ionic glassy breaking

Long-Term Durability and Reactivation of Thermochemical Heat Storage Driven by the CaO/Ca(OH)2Reversible Reaction

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Journal of Materials Science and Chemical Engineering 2017年第11期5卷 23-32页

作者： Kazuki kuwata Takehiro Esaki Daichi Iwase Hiroyuki Ito Shijie Li Xixian Yang Hongyu Huang noriyuki Kobayashi Nagoya University Nagoya Japan Integrated Technology Center Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou China

Thermochemical heat storage is a promising technology for improving thermal energy efficiency. To investigate the durability of the CaO/Ca(OH)2 reaction and develop a reactivation method, repetitive charging/discharging operation of a packed bed reactor with a thick packed bed was conducted, and variations in the discharging behavior, final conversion, and reactant activity were investigated. Owing to the formation of a deactivated sintered reactant block, the discharging time halved and the final conversion ratio decreased by the 53rd discharging operation. To enhance durability, a reactivation method using high-pressure vapor was implemented during the 54th discharging operation. Following reactivation, the final conversion increased 15%, and the discharging time tripled when compared with the discharging operation before reactivation, confirming the success of this simple reactivation method.

关键词： Thermochemical Heat Storage Durability Repetitive Reaction Reactivation CaO/Ca(OH)2 Reaction

Cardiac biomarkers in children with congenital heart disease

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World Journal of Pediatrics 2015年第4期11卷 309-315页

作者： Masaya Sugimoto Seiko kuwata Clara Kurishima Jeong Hye Kim Yoich Iwamoto Hideaki Senzaki Department of Pediatrics Asahikawa Medical UniversityAsahikawaJapan Department of Pediatric Cardiology Saitama Medical CenterSaitama Medical UniversityKawagoeJapan

Background:Most congenital heart diseases(CHDs)have specific hemodynamics,including volume and pressure overload,as well as cyanosis and pulmonary hypertension,associated with anatomical *** hemodynamic abnormalities can cause activation of neurohormones,inflammatory cytokines,fibroblasts,and vascular endothelial cells,which in turn contribute to the development of pathologic conditions such as cardiac hypertrophy,fi brosis,and cardiac cell damages and *** biomarker levels facilitates the prediction of these pathological changes,and provides information about the stress placed on the myocardial cells,the severity of the damage,the responses of neurohumoral factors,and the remodeling of the *** to the ample information on cardiac biomarkers in adult heart diseases,data from children with CHD are still *** sources:We reviewed cardiac biomarkers-specifi cally focusing on troponin as a biomarker of myocardial damage,amino-terminal procollagen type III peptide(PIIIP)as a biomarker of myocardialfi brosis and stromal remodeling,and B-type natriuretic peptide(BNP)/N-terminal proBNP as biomarkers of cardiac load and heart failure,by introducing relevant publications,including our own,on pediatric CHD patients as well as ***:Levels of highly sensitive troponin I are elevated in patients with atrial septal defects(ASDs)and ventricular septal defects(VSDs).PIIIP levels are also elevated in patients with ASD,VSD,pulmonary stenosis,and Tetralogy of *** of BNP and N-terminal proBNP levels shows good correlation with heart failure score in ***:In the treatment of children with CHD requiring delicate care,it is vital to know the specifi c degree of myocardial damage and severity of heart *** biomarkers are useful tools for ascertaining the condition of CHDs with ease and are likely to be useful in determining the appropriate care of pediatric cardiology patients.

关键词： biomarker B-type natriuretic peptide congenital heart disease procollagen type III peptide troponin