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排序方式: 共有1014条查询结果,搜索用时 46 毫秒
1.
Dr. Yoji Horii Prof. Dr. Keiichi Katoh Prof. Dr. Yuji Miyazaki Dr. Marko Damjanović Tetsu Sato Prof. Dr. Liviu Ungur Prof. Dr. Liviu F. Chibotaru Prof. Dr. Brian K. Breedlove Prof. Dr. Motohiro Nakano Prof. Dr. Wolfgang Wernsdorfer Prof. Dr. Masahiro Yamashita 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(36):8076-8082
Gd3+ complexes have been shown to undergo unusual slow magnetic relaxation processes similar to those of single-molecule magnets (SMMs), even though Gd3+ does not exhibit strong magnetic anisotropy. To reveal the origin of the slow magnetic relaxation of Gd3+ complexes, we have investigated the magnetic properties and heat capacities of two Gd3+-phthalocyaninato triple-decker complexes, one of which has intramolecular Gd3+–Gd3+ interactions and the other does not. It was found that the Gd3+–Gd3+ interactions accelerate the magnetic relaxation processes. In addition, magnetically diluted samples, prepared by doping a small amount of the Gd3+ complexes into a large amount of diamagnetic Y3+ complexes, underwent dual magnetic relaxation processes. A detailed dynamic magnetic analysis revealed that the coexistence of spin–lattice relaxation and phonon-bottleneck processes is the origin of the dual magnetic relaxation processes. 相似文献
2.
Lee V. Ya. Miyazaki S. Gapurenko O. A. Minyaev R. M. Minkin V. I. Sekiguchi A. 《Russian Chemical Bulletin》2021,70(11):2233-2235
(Thiatrisila)bicyclo[1.1.0]butane 1 quantitatively transformed under either photochemical or thermal conditions into the isomeric (thiatrisila)cyclobutene 2, which was isolated and fully characterized.
相似文献3.
Miyazaki Reona Sakaguchi Isao Hihara Takehiko 《Journal of Solid State Electrochemistry》2021,25(6):1927-1936
Journal of Solid State Electrochemistry - In the present work, the conduction ions in 15NaI∙LiBH4 are investigated by secondary ion mass spectroscopy (SIMS) and galvanostatic measurements. An... 相似文献
4.
Cover Picture: Electron–Proton Decoupling in Excited‐State Hydrogen Atom Transfer in the Gas Phase (Angew. Chem. Int. Ed. 50/2015) 下载免费PDF全文
5.
The transient recoverable deformation ratio after melt elongation at various elongational rates and maximum elongations was
investigated for pure polystyrene and for a 85 wt.% polystyrene/15 wt.% linear low density polyethylene (PS/LLDPE 85:15) blend
at a temperature of 170 oC. The ratio p of the zero shear rate viscosity of LLDPE to that of PS is p = 0.059 ≈ 1:17. Retraction of the elongated LLDPE droplets back to spheres and end-pinching is observed during recovery.
A simple additive rule is applied in order to extract the contribution of the recovery of the elongated droplets from the
total recovery of the blend. In that way, the recoverable portion of the PS/LLDPE blend induced by the interfacial tension
is determined and compared with the results of a theory based on an effective medium approximation. The effective medium approximation
reproduces well the time scale of the experimental data. In addition, the trends that the recoverable deformation increases
with elongational rate and maximum elongation are captured by the theoretical approach. 相似文献
6.
This paper introduces an elasto-plastic joint element characterised by strain hardening and softening in the analysis of dynamic
soil-structure interaction. The phenomena of separation and sliding on the contact surface between soil and structure can
be better simulated and the process can also be described. The interaction problems in a typical soil-structure system are
analyzed in terms of elasto-plastic joint element as well as elastic ones. The results show that the elasto-plastic joint
element is much better than the elastic one in modelling, especially in that the relative displacements accross the joint
element can be much greater than that of the elastic case. Separation and sliding are not only related to the coefficient
of friction and cohesion but also to their changes with plastic volumetric strain.
The project is supported by the Sciences Foundation of the Chinese Academy of Sciences and the Disaster Provention Institute
of Kyoto University (Japan). 相似文献
7.
Paulo H. P. Macaúbas Hideo Kawamoto Masaoki Takahashi Kenzo Okamoto Toshikazu Takigawa 《Rheologica Acta》2007,46(7):921-932
Shape recovery of a droplet of liquid crystalline polymer (LCP) hydroxypropylcellulose in a matrix of poly(dimethyl siloxane) subjected to a step shear strain has been studied via optical microscopy. Just after application of a large strain, the LCP droplet shape is flat ellipsoid, and then the droplet takes cylindrical shape and band texture perpendicular to the flow direction appears. The band texture fades away before emergence of poly-domain structure. In the final process with the shape of spheroid, poly-domain structure recovers very slowly. Except for the final process, the shape change is identical with that of isotropic droplet at strains smaller than 3, when the LCP viscosity in Region II is taken as an equivalent viscosity for normalization. For a 20:80 blend, the excess relaxation modulus is calculated based on the Doi-Ohta theory, taking account of the distribution of droplet size and compared with experimental modulus data. 相似文献
8.
Summary When a d.c. and a h.f. field are perpendicularly superposed in a electrical discharge (p 10–10–4 mm Hg), three types of discharge can exist, classified from the standpoint of d.c. conduction: (1) d.c. glow type, d.c.-dominant discharge with additional ionization by h.f. field; (2) space chargelimited type, the same as the conduction in the floating double probe in a plasma produced by h.f. field; (3) an intermediate stage between the first and second types, herein referred to as transition type. According to our analysis of the transition type at low pressure, the value of in high electric fields can be deduced from the measurement. 相似文献
9.
Proton Order–Disorder Phenomena in a Hydrogen‐Bonded Rhodium–η5‐Semiquinone Complex: A Possible Dielectric Response Mechanism 下载免费PDF全文
Dr. Minoru Mitsumi Kazunari Ezaki Yuuki Komatsu Prof. Dr. Koshiro Toriumi Dr. Tatsuya Miyatou Prof. Dr. Motohiro Mizuno Nobuaki Azuma Prof. Dr. Yuji Miyazaki Prof. Dr. Motohiro Nakano Prof. Dr. Yasutaka Kitagawa Dr. Takayasu Hanashima Dr. Ryoji Kiyanagi Dr. Takashi Ohhara Prof. Dr. Kazuhiro Nakasuji 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(27):9682-9696
A newly synthesized one‐dimensional (1D) hydrogen‐bonded (H‐bonded) rhodium(II)–η5‐semiquinone complex, [Cp*Rh(η5‐p‐HSQ‐Me4)]PF6 ([ 1 ]PF6; Cp*=1,2,3,4,5‐pentamethylcyclopentadienyl; HSQ=semiquinone) exhibits a paraelectric–antiferroelectric second‐order phase transition at 237.1 K. Neutron and X‐ray crystal structure analyses reveal that the H‐bonded proton is disordered over two sites in the room‐temperature (RT) phase. The phase transition would arise from this proton disorder together with rotation or libration of the Cp* ring and PF6? ion. The relative permittivity εb′ along the H‐bonded chains reaches relatively high values (ca., 130) in the RT phase. The temperature dependence of 13C CP/MAS NMR spectra demonstrates that the proton is dynamically disordered in the RT phase and that the proton exchange has already occurred in the low‐temperature (LT) phase. Rate constants for the proton exchange are estimated to be 10?4–10?6 s in the temperature range of 240–270 K. DFT calculations predict that the protonation/deprotonation of [ 1 ]+ leads to interesting hapticity changes of the semiquinone ligand accompanied by reduction/oxidation by the π‐bonded rhodium fragment, producing the stable η6‐hydroquinone complex, [Cp*Rh3+(η6‐p‐H2Q‐Me4)]2+ ([ 2 ]2+), and η4‐benzoquinone complex, [Cp*Rh+(η4‐p‐BQ‐Me4)] ([ 3 ]), respectively. Possible mechanisms leading to the dielectric response are discussed on the basis of the migration of the protonic solitons comprising of [ 2 ]2+ and [ 3 ], which would be generated in the H‐bonded chain. 相似文献
10.